From ec8ac48a606e311c3c030a408510e74df30cd073 Mon Sep 17 00:00:00 2001
From: Jeff Tao <jhtao@taosdata.com>
Date: Fri, 13 Nov 2020 12:44:53 +0000
Subject: [PATCH 01/41] return value is pointer

---
 src/sync/src/syncMain.c   | 2 +-
 src/util/tests/trefTest.c | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/sync/src/syncMain.c b/src/sync/src/syncMain.c
index 8d90315c48..4b51c770e7 100644
--- a/src/sync/src/syncMain.c
+++ b/src/sync/src/syncMain.c
@@ -1097,7 +1097,7 @@ static void syncProcessBrokenLink(void *param) {
   SSyncPeer *pPeer = param;
   SSyncNode *pNode = pPeer->pSyncNode;
 
-  if (taosAcquireRef(tsSyncRefId, pNode->rid) < 0) return;
+  if (taosAcquireRef(tsSyncRefId, pNode->rid) == NULL) return;
   pthread_mutex_lock(&(pNode->mutex));
 
   sDebug("%s, TCP link is broken(%s)", pPeer->id, strerror(errno));
diff --git a/src/util/tests/trefTest.c b/src/util/tests/trefTest.c
index 6887b24abd..454860410b 100644
--- a/src/util/tests/trefTest.c
+++ b/src/util/tests/trefTest.c
@@ -77,8 +77,8 @@ void *acquireRelease(void *param) {
     printf("a");
     
     id = random() % pSpace->refNum; 
-    code = taosAcquireRef(pSpace->rsetId, pSpace->p[id]);
-    if (code >= 0) {
+    void *p = taosAcquireRef(pSpace->rsetId, pSpace->p[id]);
+    if (p) {
       usleep(id % 5 + 1);
       taosReleaseRef(pSpace->rsetId, pSpace->p[id]);
     }

From 4c11e46075d65d1bc29a116ed9359dd36c80d421 Mon Sep 17 00:00:00 2001
From: zyyang <zyyang@taosdata.com>
Date: Wed, 18 Nov 2020 17:40:00 +0800
Subject: [PATCH 02/41] change

---
 .../com/taosdata/jdbc/rs/RestfulDriver.java   |  3 +-
 .../taosdata/jdbc/rs/RestfulDriverTest.java   | 35 ++++++++++++++++++-
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulDriver.java b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulDriver.java
index c267f660de..a07d6eb2b6 100644
--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulDriver.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulDriver.java
@@ -86,6 +86,7 @@ public class RestfulDriver extends AbstractTaosDriver {
 
     @Override
     public Logger getParentLogger() throws SQLFeatureNotSupportedException {
-        return null;
+        //TODO SQLFeatureNotSupportedException
+        throw new SQLFeatureNotSupportedException();
     }
 }
diff --git a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDriverTest.java b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDriverTest.java
index a91d1c2d6b..768eceab8e 100644
--- a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDriverTest.java
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDriverTest.java
@@ -31,10 +31,43 @@ public class RestfulDriverTest {
     }
 
     @Test
-    public void testAcceptUrl() throws SQLException {
+    public void connect() {
+
+    }
+
+    @Test
+    public void acceptsURL() throws SQLException {
         Driver driver = new RestfulDriver();
         boolean isAccept = driver.acceptsURL("jdbc:TAOS-RS://master:6041");
         Assert.assertTrue(isAccept);
+        isAccept = driver.acceptsURL("jdbc:TAOS://master:6041");
+        Assert.assertFalse(isAccept);
     }
 
+    @Test
+    public void getPropertyInfo() throws SQLException {
+        Driver driver = new RestfulDriver();
+        final String url = "";
+        DriverPropertyInfo[] propertyInfo = driver.getPropertyInfo(url, null);
+    }
+
+    @Test
+    public void getMajorVersion() {
+        Assert.assertEquals(2, new RestfulDriver().getMajorVersion());
+    }
+
+    @Test
+    public void getMinorVersion() {
+        Assert.assertEquals(0, new RestfulDriver().getMinorVersion());
+    }
+
+    @Test
+    public void jdbcCompliant() {
+        Assert.assertFalse(new RestfulDriver().jdbcCompliant());
+    }
+
+    @Test(expected = SQLFeatureNotSupportedException.class)
+    public void getParentLogger() throws SQLFeatureNotSupportedException {
+        new RestfulDriver().getParentLogger();
+    }
 }

From a8b87ce0cd79c498fc370f7c4656f335115256fd Mon Sep 17 00:00:00 2001
From: Jeff Tao <jhtao@taosdata.com>
Date: Fri, 20 Nov 2020 01:07:33 +0000
Subject: [PATCH 03/41] change applications

---
 src/query/src/qResultbuf.c |   8 +-
 src/util/inc/hash.h        |  53 ++----
 src/util/src/hash.c        | 332 ++++++++++++++++++-------------------
 src/util/src/tkvstore.c    |  19 +--
 src/vnode/src/vnodeMain.c  |  28 ++--
 5 files changed, 191 insertions(+), 249 deletions(-)

diff --git a/src/query/src/qResultbuf.c b/src/query/src/qResultbuf.c
index 2645cff678..e9ed8dc1c3 100644
--- a/src/query/src/qResultbuf.c
+++ b/src/query/src/qResultbuf.c
@@ -420,9 +420,8 @@ void destroyResultBuf(SDiskbasedResultBuf* pResultBuf) {
   unlink(pResultBuf->path);
   tfree(pResultBuf->path);
 
-  SHashMutableIterator* iter = taosHashCreateIter(pResultBuf->groupSet);
-  while(taosHashIterNext(iter)) {
-    SArray** p = (SArray**) taosHashIterGet(iter);
+  SArray** p = taosHashIterate(pResultBuf->groupSet, NULL);
+  while(p) {
     size_t n = taosArrayGetSize(*p);
     for(int32_t i = 0; i < n; ++i) {
       SPageInfo* pi = taosArrayGetP(*p, i);
@@ -431,10 +430,9 @@ void destroyResultBuf(SDiskbasedResultBuf* pResultBuf) {
     }
 
     taosArrayDestroy(*p);
+    p = taosHashIterate(pResultBuf->groupSet, p);
   }
 
-  taosHashDestroyIter(iter);
-
   tdListFree(pResultBuf->lruList);
   taosArrayDestroy(pResultBuf->emptyDummyIdList);
   taosHashCleanup(pResultBuf->groupSet);
diff --git a/src/util/inc/hash.h b/src/util/inc/hash.h
index 42bc136584..aaff48f4f8 100644
--- a/src/util/inc/hash.h
+++ b/src/util/inc/hash.h
@@ -31,16 +31,17 @@ extern "C" {
 typedef void (*_hash_free_fn_t)(void *param);
 
 typedef struct SHashNode {
-//  char             *key;
   struct SHashNode *next;
   uint32_t          hashVal;  // the hash value of key
   uint32_t          keyLen;   // length of the key
-//  char             *data;
+  uint32_t          dataLen;  // length of data
+  int8_t            count;    // reference count
+  char              data[];
 } SHashNode;
 
-#define GET_HASH_NODE_KEY(_n)  ((char*)(_n) + sizeof(SHashNode))
-#define GET_HASH_NODE_DATA(_n) ((char*)(_n) + sizeof(SHashNode) + (_n)->keyLen)
-
+#define GET_HASH_NODE_KEY(_n)  ((char*)(_n) + sizeof(SHashNode) + (_n)->dataLen)
+#define GET_HASH_NODE_DATA(_n) ((char*)(_n) + sizeof(SHashNode))
+#define GET_HASH_PNODE(_n) ((char*)(_n) - sizeof(SHashNode));
 typedef enum SHashLockTypeE {
   HASH_NO_LOCK     = 0,
   HASH_ENTRY_LOCK  = 1,
@@ -65,15 +66,6 @@ typedef struct SHashObj {
   SArray         *pMemBlock;    // memory block allocated for SHashEntry
 } SHashObj;
 
-typedef struct SHashMutableIterator {
-  SHashObj  *pHashObj;
-  int32_t    entryIndex;
-  SHashNode *pCur;
-  SHashNode *pNext;           // current node can be deleted for mutable iterator, so keep the next one before return current
-  size_t     numOfChecked;    // already check number of elements in hash table
-  size_t     numOfEntries;    // number of entries while the iterator is created
-} SHashMutableIterator;
-
 /**
  * init the hash table
  *
@@ -142,33 +134,9 @@ int32_t taosHashCondTraverse(SHashObj *pHashObj, bool (*fp)(void *, void *), voi
  */
 void taosHashCleanup(SHashObj *pHashObj);
 
-/**
- *
- * @param pHashObj
- * @return
- */
-SHashMutableIterator* taosHashCreateIter(SHashObj *pHashObj);
-
-/**
- *
- * @param iter
- * @return
- */
-bool taosHashIterNext(SHashMutableIterator *iter);
-
-/**
- *
- * @param iter
- * @return
- */
-void *taosHashIterGet(SHashMutableIterator *iter);
-
-/**
- *
- * @param iter
- * @return
- */
-void* taosHashDestroyIter(SHashMutableIterator* iter);
+/*
+void *SHashMutableIterator* taosHashCreateIter(SHashObj *pHashObj, void *);
+*/
 
 /**
  *
@@ -179,6 +147,9 @@ int32_t taosHashGetMaxOverflowLinkLength(const SHashObj *pHashObj);
 
 size_t taosHashGetMemSize(const SHashObj *pHashObj);
 
+void *taosHashIterate(SHashObj *pHashObj, void *p);
+void  taosHashCancelIterate(SHashObj *pHashObj, void *p);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/util/src/hash.c b/src/util/src/hash.c
index 03a7342497..cd9a9f7d0a 100644
--- a/src/util/src/hash.c
+++ b/src/util/src/hash.c
@@ -114,15 +114,25 @@ static SHashNode *doCreateHashNode(const void *key, size_t keyLen, const void *p
  * @param dsize   size of actual data
  * @return        hash node
  */
-static FORCE_INLINE SHashNode *doUpdateHashNode(SHashEntry* pe, SHashNode* prev, SHashNode *pNode, SHashNode *pNewNode) {
+static FORCE_INLINE SHashNode *doUpdateHashNode(SHashObj *pHashObj, SHashEntry* pe, SHashNode* prev, SHashNode *pNode, SHashNode *pNewNode) {
   assert(pNode->keyLen == pNewNode->keyLen);
+
+  pNode->count--;
   if (prev != NULL) {
     prev->next = pNewNode;
   } else {
     pe->next = pNewNode;
   }
 
-  pNewNode->next = pNode->next;
+  if (pNode->count <= 0) {
+    pNewNode->next = pNode->next;
+    DO_FREE_HASH_NODE(pNode);
+  } else {
+    pNewNode->next = pNode;    
+    pe->num++;
+    atomic_add_fetch_64(&pHashObj->size, 1);
+  }
+  
   return pNewNode;
 }
 
@@ -139,7 +149,6 @@ static void pushfrontNodeInEntryList(SHashEntry *pEntry, SHashNode *pNode);
  * @param pIter
  * @return
  */
-static SHashNode *getNextHashNode(SHashMutableIterator *pIter);
 
 SHashObj *taosHashInit(size_t capacity, _hash_fn_t fn, bool update, SHashLockTypeE type) {
   if (capacity == 0 || fn == NULL) {
@@ -244,8 +253,7 @@ int32_t taosHashPut(SHashObj *pHashObj, const void *key, size_t keyLen, void *da
   } else {
     // not support the update operation, return error
     if (pHashObj->enableUpdate) {
-      doUpdateHashNode(pe, prev, pNode, pNewNode);
-      DO_FREE_HASH_NODE(pNode);
+      doUpdateHashNode(pHashObj, pe, prev, pNode, pNewNode);
     } else {
       DO_FREE_HASH_NODE(pNewNode);
     }
@@ -335,22 +343,10 @@ int32_t taosHashRemoveWithData(SHashObj *pHashObj, const void *key, size_t keyLe
   int32_t     slot = HASH_INDEX(hashVal, pHashObj->capacity);
   SHashEntry *pe = pHashObj->hashList[slot];
 
-  // no data, return directly
-  if (pe->num == 0) {
-    __rd_unlock(&pHashObj->lock, pHashObj->type);
-    return -1;
-  }
-
   if (pHashObj->type == HASH_ENTRY_LOCK) {
     taosWLockLatch(&pe->latch);
   }
 
-  if (pe->num == 0) {
-    assert(pe->next == NULL);
-  } else {
-    assert(pe->next != NULL);
-  }
-
   // double check after locked
   if (pe->num == 0) {
     assert(pe->next == NULL);
@@ -360,37 +356,36 @@ int32_t taosHashRemoveWithData(SHashObj *pHashObj, const void *key, size_t keyLe
     return -1;
   }
 
+  int code = -1;
   SHashNode *pNode = pe->next;
-  SHashNode *pRes = NULL;
+  SHashNode *prevNode = NULL;
 
-  // remove it
-  if ((pNode->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY(pNode), key, keyLen) == 0)) {
-    pe->num -= 1;
-    pRes = pNode;
-    pe->next = pNode->next;
-  } else {
-    while (pNode->next != NULL) {
-      if (((pNode->next)->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY((pNode->next)), key, keyLen) == 0)) {
-        assert((pNode->next)->hashVal == hashVal);
-        break;
+  while (pNode) {
+    if ((pNode->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY(pNode), key, keyLen) == 0)) 
+      break;
+
+    prevNode = pNode;
+    pNode = pNode->next;
+  }
+
+  if (pNode) {
+    code = 0;  // it is found
+
+    pNode->count--;
+    if (pNode->count <= 0) {
+      if (prevNode) {
+        prevNode->next = pNode->next;
+      } else {
+        pe->next = pNode->next;
       }
+   
+      if (data) memcpy(data, GET_HASH_NODE_DATA(pNode), dsize);
 
-      pNode = pNode->next;
+      pe->num--;
+      atomic_sub_fetch_64(&pHashObj->size, 1);
+      FREE_HASH_NODE(pHashObj, pNode);
     }
-
-
-    if (pNode->next != NULL) {
-      pe->num -= 1;
-      pRes = pNode->next;
-      pNode->next = pNode->next->next;
-    }
-  }
-
-  if (pe->num == 0) {
-    assert(pe->next == NULL);
-  } else {
-    assert(pe->next != NULL);
-  }
+  } 
 
   if (pHashObj->type == HASH_ENTRY_LOCK) {
     taosWUnLockLatch(&pe->latch);
@@ -398,17 +393,7 @@ int32_t taosHashRemoveWithData(SHashObj *pHashObj, const void *key, size_t keyLe
 
   __rd_unlock(&pHashObj->lock, pHashObj->type);
 
-  if (data != NULL && pRes != NULL) {
-    memcpy(data, GET_HASH_NODE_DATA(pRes), dsize);
-  }
-
-  if (pRes != NULL) {
-    atomic_sub_fetch_64(&pHashObj->size, 1);
-    FREE_HASH_NODE(pHashObj, pRes);
-    return 0;
-  } else {
-    return -1;
-  }
+  return code;
 }
 
 int32_t taosHashCondTraverse(SHashObj *pHashObj, bool (*fp)(void *, void *), void *param) {
@@ -531,98 +516,6 @@ void taosHashCleanup(SHashObj *pHashObj) {
   free(pHashObj);
 }
 
-SHashMutableIterator *taosHashCreateIter(SHashObj *pHashObj) {
-  SHashMutableIterator *pIter = calloc(1, sizeof(SHashMutableIterator));
-  if (pIter == NULL) {
-    return NULL;
-  }
-
-  pIter->pHashObj = pHashObj;
-
-  // keep it in local variable, in case the resize operation expand the size
-  pIter->numOfEntries = pHashObj->capacity;
-  return pIter;
-}
-
-bool taosHashIterNext(SHashMutableIterator *pIter) {
-  if (pIter == NULL) {
-    return false;
-  }
-
-  size_t size = taosHashGetSize(pIter->pHashObj);
-  if (size == 0) {
-    return false;
-  }
-
-  // check the first one
-  if (pIter->numOfChecked == 0) {
-    assert(pIter->pCur == NULL && pIter->pNext == NULL);
-
-    while (1) {
-      SHashEntry *pEntry = pIter->pHashObj->hashList[pIter->entryIndex];
-      if (pEntry->num == 0) {
-        assert(pEntry->next == NULL);
-
-        pIter->entryIndex++;
-        continue;
-      }
-
-      if (pIter->pHashObj->type == HASH_ENTRY_LOCK) {
-        taosRLockLatch(&pEntry->latch);
-      }
-
-      pIter->pCur = pEntry->next;
-
-      if (pIter->pCur->next) {
-        pIter->pNext = pIter->pCur->next;
-
-        if (pIter->pHashObj->type == HASH_ENTRY_LOCK) {
-          taosRUnLockLatch(&pEntry->latch);
-        }
-      } else {
-        if (pIter->pHashObj->type == HASH_ENTRY_LOCK) {
-          taosRUnLockLatch(&pEntry->latch);
-        }
-
-        pIter->pNext = getNextHashNode(pIter);
-      }
-
-      break;
-    }
-
-    pIter->numOfChecked++;
-    return true;
-  } else {
-    assert(pIter->pCur != NULL);
-    if (pIter->pNext) {
-      pIter->pCur = pIter->pNext;
-    } else {  // no more data in the hash list
-      return false;
-    }
-
-    pIter->numOfChecked++;
-
-    if (pIter->pCur->next) {
-      pIter->pNext = pIter->pCur->next;
-    } else {
-      pIter->pNext = getNextHashNode(pIter);
-    }
-
-    return true;
-  }
-}
-
-void *taosHashIterGet(SHashMutableIterator *iter) { return (iter == NULL) ? NULL : GET_HASH_NODE_DATA(iter->pCur); }
-
-void *taosHashDestroyIter(SHashMutableIterator *iter) {
-  if (iter == NULL) {
-    return NULL;
-  }
-
-  free(iter);
-  return NULL;
-}
-
 // for profile only
 int32_t taosHashGetMaxOverflowLinkLength(const SHashObj *pHashObj) {
   if (pHashObj == NULL || pHashObj->size == 0) {
@@ -759,6 +652,8 @@ SHashNode *doCreateHashNode(const void *key, size_t keyLen, const void *pData, s
 
   pNewNode->keyLen = (uint32_t)keyLen;
   pNewNode->hashVal = hashVal;
+  pNewNode->dataLen = dsize;
+  pNewNode->count = 1;
 
   memcpy(GET_HASH_NODE_DATA(pNewNode), pData, dsize);
   memcpy(GET_HASH_NODE_KEY(pNewNode), key, keyLen);
@@ -775,35 +670,6 @@ void pushfrontNodeInEntryList(SHashEntry *pEntry, SHashNode *pNode) {
   pEntry->num += 1;
 }
 
-SHashNode *getNextHashNode(SHashMutableIterator *pIter) {
-  assert(pIter != NULL);
-
-  pIter->entryIndex++;
-  SHashNode *p = NULL;
-
-  while (pIter->entryIndex < pIter->numOfEntries) {
-    SHashEntry *pEntry = pIter->pHashObj->hashList[pIter->entryIndex];
-    if (pEntry->num == 0) {
-      pIter->entryIndex++;
-      continue;
-    }
-
-    if (pIter->pHashObj->type == HASH_ENTRY_LOCK) {
-      taosRLockLatch(&pEntry->latch);
-    }
-
-    p = pEntry->next;
-
-    if (pIter->pHashObj->type == HASH_ENTRY_LOCK) {
-      taosRUnLockLatch(&pEntry->latch);
-    }
-
-    return p;
-  }
-
-  return NULL;
-}
-
 size_t taosHashGetMemSize(const SHashObj *pHashObj) {
   if (pHashObj == NULL) {
     return 0;
@@ -811,3 +677,119 @@ size_t taosHashGetMemSize(const SHashObj *pHashObj) {
 
   return (pHashObj->capacity * (sizeof(SHashEntry) + POINTER_BYTES)) + sizeof(SHashNode) * taosHashGetSize(pHashObj) + sizeof(SHashObj);
 }
+
+// release the pNode, return next pNode, and lock the current entry
+static void *taosHashReleaseNode(SHashObj *pHashObj, void *p, int *slot) {
+
+  SHashNode *pOld = (SHashNode *)GET_HASH_PNODE(p);
+  SHashNode *prevNode = NULL;
+
+  *slot = HASH_INDEX(pOld->hashVal, pHashObj->capacity);
+  SHashEntry *pe = pHashObj->hashList[*slot];
+
+  // lock entry
+  if (pHashObj->type == HASH_ENTRY_LOCK) {
+    taosWLockLatch(&pe->latch);
+  }
+
+  SHashNode *pNode = pe->next;
+
+  while (pNode) {
+    if (pNode == pOld) 
+      break;
+
+    prevNode = pNode;
+    pNode = pNode->next;
+  }
+
+  if (pNode) {
+    pNode = pNode->next;
+    pOld->count--;
+    if (pOld->count <=0) {
+      if (prevNode) {
+        prevNode->next = pOld->next;
+      } else {
+        pe->next = pOld->next;
+      }
+   
+      pe->num--;
+      atomic_sub_fetch_64(&pHashObj->size, 1);
+      FREE_HASH_NODE(pHashObj, pOld);
+    } 
+  } else {
+    uError("pNode:%p data:%p is not there!!!", pNode, p);
+  }
+
+  return pNode;
+}
+
+void *taosHashIterate(SHashObj *pHashObj, void *p) {
+  if (pHashObj == NULL) return NULL; 
+
+  int  slot = 0;
+  char *data = NULL;
+
+  // only add the read lock to disable the resize process
+  __rd_lock(&pHashObj->lock, pHashObj->type);
+
+  SHashNode *pNode = NULL;
+  if (p) {
+    pNode = taosHashReleaseNode(pHashObj, p, &slot);
+    if (pNode == NULL) {
+      SHashEntry *pe = pHashObj->hashList[slot];
+      if (pHashObj->type == HASH_ENTRY_LOCK) {
+        taosWUnLockLatch(&pe->latch);
+      } 
+
+      slot = slot + 1;
+    }
+  }
+
+  if (pNode == NULL) {
+    for (; slot < pHashObj->capacity; ++slot) {
+      SHashEntry *pe = pHashObj->hashList[slot];
+
+      // lock entry
+      if (pHashObj->type == HASH_ENTRY_LOCK) {
+        taosWLockLatch(&pe->latch);
+      }
+
+      pNode = pe->next;
+      if (pNode) break;
+
+      if (pHashObj->type == HASH_ENTRY_LOCK) {
+        taosWUnLockLatch(&pe->latch);
+      } 
+    }
+  }
+
+  if (pNode) {
+    SHashEntry *pe = pHashObj->hashList[slot];
+    pNode->count++;
+    data = GET_HASH_NODE_DATA(pNode);
+    if (pHashObj->type == HASH_ENTRY_LOCK) {
+      taosWUnLockLatch(&pe->latch);
+    } 
+  }
+
+  __rd_unlock(&pHashObj->lock, pHashObj->type);
+  return data;
+
+}
+
+void taosHashCancelIterate(SHashObj *pHashObj, void *p) {
+  if (pHashObj == NULL || p == NULL) return;
+
+  // only add the read lock to disable the resize process
+  __rd_lock(&pHashObj->lock, pHashObj->type);
+
+  int slot;
+  taosHashReleaseNode(pHashObj, p, &slot);
+
+  SHashEntry *pe = pHashObj->hashList[slot];
+  if (pHashObj->type == HASH_ENTRY_LOCK) {
+    taosWUnLockLatch(&pe->latch);
+  } 
+
+  __rd_unlock(&pHashObj->lock, pHashObj->type);
+}
diff --git a/src/util/src/tkvstore.c b/src/util/src/tkvstore.c
index 31641ac9a7..2b1d13c78b 100644
--- a/src/util/src/tkvstore.c
+++ b/src/util/src/tkvstore.c
@@ -529,7 +529,7 @@ static int tdRestoreKVStore(SKVStore *pStore) {
   void *                buf = NULL;
   int64_t               maxBufSize = 0;
   SKVRecord             rInfo = {0};
-  SHashMutableIterator *pIter = NULL;
+  SKVRecord            *pRecord = NULL;
 
   ASSERT(TD_KVSTORE_HEADER_SIZE == lseek(pStore->fd, 0, SEEK_CUR));
   ASSERT(pStore->info.size == TD_KVSTORE_HEADER_SIZE);
@@ -582,16 +582,8 @@ static int tdRestoreKVStore(SKVStore *pStore) {
     goto _err;
   }
 
-  pIter = taosHashCreateIter(pStore->map);
-  if (pIter == NULL) {
-    uError("failed to create hash iter while opening KV store %s", pStore->fname);
-    terrno = TSDB_CODE_COM_OUT_OF_MEMORY;
-    goto _err;
-  }
-
-  while (taosHashIterNext(pIter)) {
-    SKVRecord *pRecord = taosHashIterGet(pIter);
-
+  pRecord = taosHashIterate(pStore->map, NULL);
+  while (pRecord) {
     if (lseek(pStore->fd, (off_t)(pRecord->offset + sizeof(SKVRecord)), SEEK_SET) < 0) {
       uError("failed to lseek file %s since %s, offset %" PRId64, pStore->fname, strerror(errno), pRecord->offset);
       terrno = TAOS_SYSTEM_ERROR(errno);
@@ -613,16 +605,17 @@ static int tdRestoreKVStore(SKVStore *pStore) {
         goto _err;
       }
     }
+
+    pRecord = taosHashIterate(pStore->map, pRecord);
   }
 
   if (pStore->aFunc) (*pStore->aFunc)(pStore->appH);
 
-  taosHashDestroyIter(pIter);
   tfree(buf);
   return 0;
 
 _err:
-  taosHashDestroyIter(pIter);
+  taosHashCancelIterate(pStore->map, pRecord);
   tfree(buf);
   return -1;
 }
diff --git a/src/vnode/src/vnodeMain.c b/src/vnode/src/vnodeMain.c
index 7447acc488..e3eb35ea32 100644
--- a/src/vnode/src/vnodeMain.c
+++ b/src/vnode/src/vnodeMain.c
@@ -517,11 +517,10 @@ static void vnodeBuildVloadMsg(SVnodeObj *pVnode, SStatusMsg *pStatus) {
 }
 
 int32_t vnodeGetVnodeList(int32_t vnodeList[], int32_t *numOfVnodes) {
-  SHashMutableIterator *pIter = taosHashCreateIter(tsVnodesHash);
-  while (taosHashIterNext(pIter)) {
-    SVnodeObj **pVnode = taosHashIterGet(pIter);
-    if (pVnode == NULL) continue;
-    if (*pVnode == NULL) continue;
+  void *pIter = taosHashIterate(tsVnodesHash, NULL);
+  while (pIter) {
+    SVnodeObj **pVnode = pIter;
+    if (*pVnode) {
 
     (*numOfVnodes)++;
     if (*numOfVnodes >= TSDB_MAX_VNODES) {
@@ -530,25 +529,24 @@ int32_t vnodeGetVnodeList(int32_t vnodeList[], int32_t *numOfVnodes) {
     } else {
       vnodeList[*numOfVnodes - 1] = (*pVnode)->vgId;
     }
-  }
 
-  taosHashDestroyIter(pIter);
+    }
+
+    pIter = taosHashIterate(tsVnodesHash, pIter);    
+  }
   return TSDB_CODE_SUCCESS;
 }
 
 void vnodeBuildStatusMsg(void *param) {
   SStatusMsg *pStatus = param;
-  SHashMutableIterator *pIter = taosHashCreateIter(tsVnodesHash);
-
-  while (taosHashIterNext(pIter)) {
-    SVnodeObj **pVnode = taosHashIterGet(pIter);
-    if (pVnode == NULL) continue;
-    if (*pVnode == NULL) continue;
 
+  void *pIter = taosHashIterate(tsVnodesHash, NULL);
+  while (pIter) {
+    SVnodeObj **pVnode = pIter; 
+    if (*pVnode) { 
     vnodeBuildVloadMsg(*pVnode, pStatus);
+    }
   }
-
-  taosHashDestroyIter(pIter);
 }
 
 void vnodeSetAccess(SVgroupAccess *pAccess, int32_t numOfVnodes) {

From 3e43a6533189e060a5e7f848959fd0bda55685da Mon Sep 17 00:00:00 2001
From: Shengliang Guan <slguan@taosdata.com>
Date: Sat, 21 Nov 2020 20:45:06 +0800
Subject: [PATCH 04/41] TD-1983 change hash in mnode

---
 src/balance/src/balance.c    | 40 ++++++++++++------------------
 src/mnode/inc/mnodeAcct.h    |  1 +
 src/mnode/inc/mnodeDb.h      |  1 +
 src/mnode/inc/mnodeDnode.h   |  1 +
 src/mnode/inc/mnodeMnode.h   |  1 +
 src/mnode/inc/mnodeSdb.h     |  6 ++---
 src/mnode/inc/mnodeShow.h    |  2 ++
 src/mnode/inc/mnodeTable.h   |  2 ++
 src/mnode/inc/mnodeUser.h    |  1 +
 src/mnode/inc/mnodeVgroup.h  |  1 +
 src/mnode/src/mnodeAcct.c    |  6 +++--
 src/mnode/src/mnodeCluster.c |  8 +++++-
 src/mnode/src/mnodeDb.c      | 12 +++++----
 src/mnode/src/mnodeDnode.c   | 23 +++++++++---------
 src/mnode/src/mnodeMnode.c   |  9 ++++---
 src/mnode/src/mnodeProfile.c | 24 +++++++++---------
 src/mnode/src/mnodeSdb.c     | 36 ++++++++++++---------------
 src/mnode/src/mnodeShow.c    |  9 ++++++-
 src/mnode/src/mnodeTable.c   | 47 ++++++++++++++++++------------------
 src/mnode/src/mnodeUser.c    |  9 ++++---
 src/mnode/src/mnodeVgroup.c  | 15 +++++-------
 src/vnode/src/vnodeMain.c    |  7 +++---
 tests/script/basicSuite.sim  |  1 -
 23 files changed, 139 insertions(+), 123 deletions(-)

diff --git a/src/balance/src/balance.c b/src/balance/src/balance.c
index df78f4fe27..b172867929 100644
--- a/src/balance/src/balance.c
+++ b/src/balance/src/balance.c
@@ -162,7 +162,6 @@ int32_t balanceAllocVnodes(SVgObj *pVgroup) {
              pDnode->openVnodes, pDnode->diskAvailable, pDnode->alternativeRole);
       mnodeDecDnodeRef(pDnode);
     }
-    sdbFreeIter(pIter);
 
     if (mnodeGetOnlineDnodesNum() == 0) {
       return TSDB_CODE_MND_NOT_READY;
@@ -377,15 +376,13 @@ static bool balanceMonitorBalance() {
                  srcScore, pDestDnode->score, destScore);
           balanceAddVnode(pVgroup, pSrcDnode, pDestDnode);
           mnodeDecVgroupRef(pVgroup);
-          sdbFreeIter(pIter);
+          mnodeCancelGetNextVgroup(pIter);
           return true;
         }
       }
 
       mnodeDecVgroupRef(pVgroup);
     }
-
-    sdbFreeIter(pIter);
   }
 
   return false;
@@ -413,8 +410,6 @@ void balanceReset() {
     mnodeDecDnodeRef(pDnode);
   }
 
-  sdbFreeIter(pIter);
-
   tsAccessSquence = 0;
 }
 
@@ -443,12 +438,11 @@ static int32_t balanceMonitorVgroups() {
 
     mnodeDecVgroupRef(pVgroup);
     if (code == TSDB_CODE_SUCCESS) {
+      mnodeCancelGetNextVgroup(pIter);
       break;
     }
   }
 
-  sdbFreeIter(pIter);
-
   return hasUpdatingVgroup;
 }
 
@@ -465,11 +459,12 @@ static bool balanceMonitorDnodeDropping(SDnodeObj *pDnode) {
     hasThisDnode = balanceCheckDnodeInVgroup(pDnode, pVgroup);
     mnodeDecVgroupRef(pVgroup);
 
-    if (hasThisDnode) break;
+    if (hasThisDnode) {
+      mnodeCancelGetNextVgroup(pIter);
+      break;
+    }
   }
 
-  sdbFreeIter(pIter);
-
   if (!hasThisDnode) {
     mInfo("dnode:%d, dropped for all vnodes are moving to other dnodes", pDnode->dnodeId);
     mnodeDropDnode(pDnode, NULL);
@@ -499,20 +494,18 @@ static bool balanceMontiorDropping() {
       pDnode->status = TAOS_DN_STATUS_DROPPING;
       mnodeUpdateDnode(pDnode);
       mnodeDecDnodeRef(pDnode);
-      sdbFreeIter(pIter);
+      mnodeCancelGetNextDnode(pIter);
       return true;
     }
 
     if (pDnode->status == TAOS_DN_STATUS_DROPPING) {
       bool ret = balanceMonitorDnodeDropping(pDnode);
       mnodeDecDnodeRef(pDnode);
-      sdbFreeIter(pIter);
+      mnodeCancelGetNextDnode(pIter);
       return ret;
     }
   }
 
-  sdbFreeIter(pIter);
-
   return false;
 }
 
@@ -556,8 +549,6 @@ static void balanceSetVgroupOffline(SDnodeObj* pDnode) {
     }
     mnodeDecVgroupRef(pVgroup);
   }
-
-  sdbFreeIter(pIter);
 }
 
 static void balanceCheckDnodeAccess() {
@@ -578,8 +569,6 @@ static void balanceCheckDnodeAccess() {
     }
     mnodeDecDnodeRef(pDnode);
   }
-
-  sdbFreeIter(pIter);
 }
 
 static void balanceProcessBalanceTimer(void *handle, void *tmrId) {
@@ -630,6 +619,7 @@ void balanceAsyncNotify() {
 int32_t balanceInit() {
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_SCORES, balanceGetScoresMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_SCORES, balanceRetrieveScores);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_SCORES, mnodeCancelGetNextDnode);
   
   pthread_mutex_init(&tsBalanceMutex, NULL);
   balanceInitDnodeList();
@@ -667,8 +657,6 @@ int32_t balanceDropDnode(SDnodeObj *pDnode) {
     mnodeDecDnodeRef(pTempDnode);
   }
 
-  sdbFreeIter(pIter);
-
   if (pDnode->openVnodes > totalFreeVnodes) {
     mError("dnode:%d, openVnodes:%d totalFreeVnodes:%d no enough dnodes", pDnode->dnodeId, pDnode->openVnodes, totalFreeVnodes);
     return TSDB_CODE_MND_NO_ENOUGH_DNODES;
@@ -780,8 +768,12 @@ void balanceAccquireDnodeList() {
   SDnodeObj *pDnode = NULL;
   int32_t    dnodeIndex = 0;
 
-  while (1) {  
-    if (dnodeIndex >= dnodesNum) break;
+  while (1) {
+    if (dnodeIndex >= dnodesNum) {
+      mnodeCancelGetNextDnode(pIter);
+      break;
+    }
+
     pIter = mnodeGetNextDnode(pIter, &pDnode);
     if (pDnode == NULL) break;
     if (pDnode->status == TAOS_DN_STATUS_OFFLINE) {
@@ -802,8 +794,6 @@ void balanceAccquireDnodeList() {
     dnodeIndex++;
   }
 
-  sdbFreeIter(pIter);
-
   tsBalanceDnodeListSize = dnodeIndex;
 }
 
diff --git a/src/mnode/inc/mnodeAcct.h b/src/mnode/inc/mnodeAcct.h
index 744a62f948..595dcca413 100644
--- a/src/mnode/inc/mnodeAcct.h
+++ b/src/mnode/inc/mnodeAcct.h
@@ -27,6 +27,7 @@ void    mnodeCleanupAccts();
 void    mnodeGetStatOfAllAcct(SAcctInfo* pAcctInfo);
 void *  mnodeGetAcct(char *acctName);
 void *  mnodeGetNextAcct(void *pIter, SAcctObj **pAcct);
+void    mnodeCancelGetNextAcct(void *pIter);
 void    mnodeIncAcctRef(SAcctObj *pAcct);
 void    mnodeDecAcctRef(SAcctObj *pAcct);
 void    mnodeAddDbToAcct(SAcctObj *pAcct, SDbObj *pDb);
diff --git a/src/mnode/inc/mnodeDb.h b/src/mnode/inc/mnodeDb.h
index 7cbd08ed92..9354b923d7 100644
--- a/src/mnode/inc/mnodeDb.h
+++ b/src/mnode/inc/mnodeDb.h
@@ -34,6 +34,7 @@ int64_t mnodeGetDbNum();
 SDbObj *mnodeGetDb(char *db);
 SDbObj *mnodeGetDbByTableId(char *db);
 void *  mnodeGetNextDb(void *pIter, SDbObj **pDb);
+void    mnodeCancelGetNextDb(void *pIter);
 void    mnodeIncDbRef(SDbObj *pDb);
 void    mnodeDecDbRef(SDbObj *pDb);
 bool    mnodeCheckIsMonitorDB(char *db, char *monitordb);
diff --git a/src/mnode/inc/mnodeDnode.h b/src/mnode/inc/mnodeDnode.h
index b6ddb7a9bf..8bc29ef9ef 100644
--- a/src/mnode/inc/mnodeDnode.h
+++ b/src/mnode/inc/mnodeDnode.h
@@ -65,6 +65,7 @@ int32_t mnodeGetDnodesNum();
 int32_t mnodeGetOnlinDnodesCpuCoreNum();
 int32_t mnodeGetOnlineDnodesNum();
 void *  mnodeGetNextDnode(void *pIter, SDnodeObj **pDnode);
+void    mnodeCancelGetNextDnode(void *pIter);
 void    mnodeIncDnodeRef(SDnodeObj *pDnode);
 void    mnodeDecDnodeRef(SDnodeObj *pDnode);
 void *  mnodeGetDnode(int32_t dnodeId);
diff --git a/src/mnode/inc/mnodeMnode.h b/src/mnode/inc/mnodeMnode.h
index a28a03ea40..10cbcebe22 100644
--- a/src/mnode/inc/mnodeMnode.h
+++ b/src/mnode/inc/mnodeMnode.h
@@ -38,6 +38,7 @@ void    mnodeDropMnodeLocal(int32_t dnodeId);
 void *  mnodeGetMnode(int32_t mnodeId);
 int32_t mnodeGetMnodesNum();
 void *  mnodeGetNextMnode(void *pIter, struct SMnodeObj **pMnode);
+void    mnodeCancelGetNextMnode(void *pIter);
 void    mnodeIncMnodeRef(struct SMnodeObj *pMnode);
 void    mnodeDecMnodeRef(struct SMnodeObj *pMnode);
 
diff --git a/src/mnode/inc/mnodeSdb.h b/src/mnode/inc/mnodeSdb.h
index 29d8cf1207..81629ede78 100644
--- a/src/mnode/inc/mnodeSdb.h
+++ b/src/mnode/inc/mnodeSdb.h
@@ -92,9 +92,9 @@ int32_t sdbDeleteRow(SSdbRow *pRow);
 int32_t sdbUpdateRow(SSdbRow *pRow);
 int32_t sdbInsertRowToQueue(SSdbRow *pRow);
 
-void    *sdbGetRow(void *pTable, void *key);
-void    *sdbFetchRow(void *pTable, void *pIter, void **ppRow);
-void     sdbFreeIter(void *pIter);
+void *   sdbGetRow(void *pTable, void *key);
+void *   sdbFetchRow(void *pTable, void *pIter, void **ppRow);
+void     sdbFreeIter(void *pTable, void *pIter);
 void     sdbIncRef(void *pTable, void *pRow);
 void     sdbDecRef(void *pTable, void *pRow);
 int64_t  sdbGetNumOfRows(void *pTable);
diff --git a/src/mnode/inc/mnodeShow.h b/src/mnode/inc/mnodeShow.h
index da66e71678..f985fe792d 100644
--- a/src/mnode/inc/mnodeShow.h
+++ b/src/mnode/inc/mnodeShow.h
@@ -26,8 +26,10 @@ void    mnodeCleanUpShow();
 
 typedef int32_t (*SShowMetaFp)(STableMetaMsg *pMeta, SShowObj *pShow, void *pConn);
 typedef int32_t (*SShowRetrieveFp)(SShowObj *pShow, char *data, int32_t rows, void *pConn);
+typedef void    (*SShowFreeIterFp)(void *pIter);
 void mnodeAddShowMetaHandle(uint8_t showType, SShowMetaFp fp);
 void mnodeAddShowRetrieveHandle(uint8_t showType, SShowRetrieveFp fp);
+void mnodeAddShowFreeIterHandle(uint8_t msgType, SShowFreeIterFp fp);
 void mnodeVacuumResult(char *data, int32_t numOfCols, int32_t rows, int32_t capacity, SShowObj *pShow);
 
 #ifdef __cplusplus
diff --git a/src/mnode/inc/mnodeTable.h b/src/mnode/inc/mnodeTable.h
index 7c0077aa60..bf04f26a90 100644
--- a/src/mnode/inc/mnodeTable.h
+++ b/src/mnode/inc/mnodeTable.h
@@ -31,6 +31,8 @@ void    mnodeIncTableRef(void *pTable);
 void    mnodeDecTableRef(void *pTable);
 void *  mnodeGetNextChildTable(void *pIter, SCTableObj **pTable);
 void *  mnodeGetNextSuperTable(void *pIter, SSTableObj **pTable);
+void    mnodeCancelGetNextChildTable(void *pIter);
+void    mnodeCancelGetNextSuperTable(void *pIter);
 void    mnodeDropAllChildTables(SDbObj *pDropDb);
 void    mnodeDropAllSuperTables(SDbObj *pDropDb);
 void    mnodeDropAllChildTablesInVgroups(SVgObj *pVgroup);
diff --git a/src/mnode/inc/mnodeUser.h b/src/mnode/inc/mnodeUser.h
index 073460f9d3..156bc7aaeb 100644
--- a/src/mnode/inc/mnodeUser.h
+++ b/src/mnode/inc/mnodeUser.h
@@ -25,6 +25,7 @@ int32_t   mnodeInitUsers();
 void      mnodeCleanupUsers();
 SUserObj *mnodeGetUser(char *name);
 void *    mnodeGetNextUser(void *pIter, SUserObj **pUser);
+void      mnodeCancelGetNextUser(void *pIter);
 void      mnodeIncUserRef(SUserObj *pUser);
 void      mnodeDecUserRef(SUserObj *pUser);
 SUserObj *mnodeGetUserFromConn(void *pConn);
diff --git a/src/mnode/inc/mnodeVgroup.h b/src/mnode/inc/mnodeVgroup.h
index 0e6d9dfde4..ee9ec7ae93 100644
--- a/src/mnode/inc/mnodeVgroup.h
+++ b/src/mnode/inc/mnodeVgroup.h
@@ -34,6 +34,7 @@ void    mnodeDropAllDnodeVgroups(SDnodeObj *pDropDnode);
 //void  mnodeUpdateAllDbVgroups(SDbObj *pAlterDb);
 
 void *  mnodeGetNextVgroup(void *pIter, SVgObj **pVgroup);
+void    mnodeCancelGetNextVgroup(void *pIter);
 void    mnodeUpdateVgroup(SVgObj *pVgroup);
 void    mnodeUpdateVgroupStatus(SVgObj *pVgroup, SDnodeObj *pDnode, SVnodeLoad *pVload);
 void    mnodeCheckUnCreatedVgroup(SDnodeObj *pDnode, SVnodeLoad *pVloads, int32_t openVnodes);
diff --git a/src/mnode/src/mnodeAcct.c b/src/mnode/src/mnodeAcct.c
index 9fff2f0229..3da889b284 100644
--- a/src/mnode/src/mnodeAcct.c
+++ b/src/mnode/src/mnodeAcct.c
@@ -144,7 +144,6 @@ void mnodeGetStatOfAllAcct(SAcctInfo* pAcctInfo) {
     pAcctInfo->numOfTimeSeries += pAcct->acctInfo.numOfTimeSeries;
     mnodeDecAcctRef(pAcct);
   }
-  sdbFreeIter(pIter);
 
   SVgObj *pVgroup = NULL;
   pIter = NULL;
@@ -158,7 +157,6 @@ void mnodeGetStatOfAllAcct(SAcctInfo* pAcctInfo) {
     pAcctInfo->totalPoints += pVgroup->pointsWritten;
     mnodeDecVgroupRef(pVgroup);
   }
-  sdbFreeIter(pIter);
 }
 
 void *mnodeGetAcct(char *name) {
@@ -169,6 +167,10 @@ void *mnodeGetNextAcct(void *pIter, SAcctObj **pAcct) {
   return sdbFetchRow(tsAcctSdb, pIter, (void **)pAcct); 
 }
 
+void mnodeCancelGetNextAcct(void *pIter) {
+  sdbFreeIter(tsAcctSdb, pIter);
+}
+
 void mnodeIncAcctRef(SAcctObj *pAcct) {
   sdbIncRef(tsAcctSdb, pAcct);
 }
diff --git a/src/mnode/src/mnodeCluster.c b/src/mnode/src/mnodeCluster.c
index 5be67e4ad9..839407c5b0 100644
--- a/src/mnode/src/mnodeCluster.c
+++ b/src/mnode/src/mnodeCluster.c
@@ -31,6 +31,7 @@ static int32_t mnodeCreateCluster();
 
 static int32_t mnodeGetClusterMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pConn);
 static int32_t mnodeRetrieveClusters(SShowObj *pShow, char *data, int32_t rows, void *pConn);
+static void    mnodeCancelGetNextCluster(void *pIter);
 
 static int32_t mnodeClusterActionDestroy(SSdbRow *pRow) {
   tfree(pRow->pObj);
@@ -108,6 +109,7 @@ int32_t mnodeInitCluster() {
 
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_CLUSTER, mnodeGetClusterMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_CLUSTER, mnodeRetrieveClusters);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_CLUSTER, mnodeCancelGetNextCluster);
 
   mDebug("table:%s, hash is created", desc.name);
   return TSDB_CODE_SUCCESS;
@@ -122,6 +124,10 @@ void *mnodeGetNextCluster(void *pIter, SClusterObj **pCluster) {
   return sdbFetchRow(tsClusterSdb, pIter, (void **)pCluster); 
 }
 
+void mnodeCancelGetNextCluster(void *pIter) {
+  sdbFreeIter(tsClusterSdb, pIter);
+}
+
 void mnodeIncClusterRef(SClusterObj *pCluster) {
   sdbIncRef(tsClusterSdb, pCluster);
 }
@@ -167,7 +173,7 @@ void mnodeUpdateClusterId() {
   }
 
   mnodeDecClusterRef(pCluster);
-  sdbFreeIter(pIter);
+  mnodeCancelGetNextCluster(pIter);
 }
 
 static int32_t mnodeGetClusterMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pConn) {
diff --git a/src/mnode/src/mnodeDb.c b/src/mnode/src/mnodeDb.c
index d121208447..77f3b93eb1 100644
--- a/src/mnode/src/mnodeDb.c
+++ b/src/mnode/src/mnodeDb.c
@@ -171,6 +171,7 @@ int32_t mnodeInitDbs() {
   mnodeAddWriteMsgHandle(TSDB_MSG_TYPE_CM_DROP_DB, mnodeProcessDropDbMsg);
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_DB, mnodeGetDbMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_DB, mnodeRetrieveDbs);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_DB, mnodeCancelGetNextDb);
   
   mDebug("table:dbs table is created");
   return 0;
@@ -180,6 +181,10 @@ void *mnodeGetNextDb(void *pIter, SDbObj **pDb) {
   return sdbFetchRow(tsDbSdb, pIter, (void **)pDb);
 }
 
+void mnodeCancelGetNextDb(void *pIter) {
+  sdbFreeIter(tsDbSdb, pIter);
+}
+
 SDbObj *mnodeGetDb(char *db) {
   return (SDbObj *)sdbGetRow(tsDbSdb, db);
 }
@@ -986,8 +991,8 @@ static int32_t mnodeAlterDbCb(SMnodeMsg *pMsg, int32_t code) {
   SDbObj *pDb = pMsg->pDb;
 
   void *pIter = NULL;
-  while (1) {
-    SVgObj *pVgroup = NULL;
+  SVgObj *pVgroup = NULL;
+    while (1) {
     pIter = mnodeGetNextVgroup(pIter, &pVgroup);
     if (pVgroup == NULL) break;
     if (pVgroup->pDb == pDb) {
@@ -995,7 +1000,6 @@ static int32_t mnodeAlterDbCb(SMnodeMsg *pMsg, int32_t code) {
     }
     mnodeDecVgroupRef(pVgroup);
   }
-  sdbFreeIter(pIter);
 
   mDebug("db:%s, all vgroups is altered", pDb->name);
   mLInfo("db:%s, is alterd by %s", pDb->name, mnodeGetUserFromMsg(pMsg));
@@ -1146,7 +1150,5 @@ void  mnodeDropAllDbs(SAcctObj *pAcct)  {
     mnodeDecDbRef(pDb);
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("acct:%s, all dbs:%d is dropped from sdb", pAcct->user, numOfDbs);
 }
diff --git a/src/mnode/src/mnodeDnode.c b/src/mnode/src/mnodeDnode.c
index f76533c760..0e9b56e459 100644
--- a/src/mnode/src/mnodeDnode.c
+++ b/src/mnode/src/mnodeDnode.c
@@ -206,6 +206,7 @@ int32_t mnodeInitDnodes() {
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_VNODES, mnodeRetrieveVnodes);
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_DNODE, mnodeGetDnodeMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_DNODE, mnodeRetrieveDnodes);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_DNODE, mnodeCancelGetNextDnode);
  
   mDebug("table:dnodes table is created");
   return 0;
@@ -223,6 +224,10 @@ void *mnodeGetNextDnode(void *pIter, SDnodeObj **pDnode) {
   return sdbFetchRow(tsDnodeSdb, pIter, (void **)pDnode); 
 }
 
+void mnodeCancelGetNextDnode(void *pIter) {
+  sdbFreeIter(tsDnodeSdb, pIter);
+}
+
 int32_t mnodeGetDnodesNum() {
   return sdbGetNumOfRows(tsDnodeSdb);
 }
@@ -241,8 +246,6 @@ int32_t mnodeGetOnlinDnodesCpuCoreNum() {
     mnodeDecDnodeRef(pDnode);
   }
 
-  sdbFreeIter(pIter);
-
   if (cpuCores < 2) cpuCores = 2;
   return cpuCores;
 }
@@ -259,8 +262,6 @@ int32_t mnodeGetOnlineDnodesNum() {
     mnodeDecDnodeRef(pDnode);
   }
 
-  sdbFreeIter(pIter);
-
   return onlineDnodes;
 }
 
@@ -276,13 +277,12 @@ void *mnodeGetDnodeByEp(char *ep) {
     pIter = mnodeGetNextDnode(pIter, &pDnode);
     if (pDnode == NULL) break;
     if (strcmp(ep, pDnode->dnodeEp) == 0) {
-      sdbFreeIter(pIter);
+      mnodeCancelGetNextDnode(pIter);
       return pDnode;
     }
     mnodeDecDnodeRef(pDnode);
   }
 
-  sdbFreeIter(pIter);
 
   return NULL;
 }
@@ -464,7 +464,10 @@ static void mnodeUpdateDnodeEps() {
   while (1) {
     pIter = mnodeGetNextDnode(pIter, &pDnode);
     if (pDnode == NULL) break;
-    if (dnodesNum >= totalDnodes) break;
+    if (dnodesNum >= totalDnodes) {
+      mnodeCancelGetNextDnode(pIter);
+      break;
+    }
 
     SDnodeEp *pEp = &tsDnodeEps->dnodeEps[dnodesNum];
     dnodesNum++;
@@ -474,7 +477,6 @@ static void mnodeUpdateDnodeEps() {
     mnodeDecDnodeRef(pDnode);
   }
 
-  sdbFreeIter(pIter);
   pthread_mutex_unlock(&tsDnodeEpsMutex);
 }
 
@@ -1100,7 +1102,7 @@ static int32_t mnodeGetVnodeMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pC
     pDnode = mnodeGetDnodeByEp(pShow->payload);
   } else {
     void *pIter = mnodeGetNextDnode(NULL, (SDnodeObj **)&pDnode);
-    sdbFreeIter(pIter);
+    mnodeCancelGetNextDnode(pIter);
   }
 
   if (pDnode != NULL) {
@@ -1148,7 +1150,6 @@ static int32_t mnodeRetrieveVnodes(SShowObj *pShow, char *data, int32_t rows, vo
 
       mnodeDecVgroupRef(pVgroup);
     }
-    sdbFreeIter(pIter);
   } else {
     numOfRows = 0;
   }
@@ -1217,8 +1218,6 @@ int32_t balanceAllocVnodes(SVgObj *pVgroup) {
     mnodeDecDnodeRef(pDnode);
   }
 
-  sdbFreeIter(pIter);
-
   if (pSelDnode == NULL) {
     mError("failed to alloc vnode to vgroup");
     return TSDB_CODE_MND_NO_ENOUGH_DNODES;
diff --git a/src/mnode/src/mnodeMnode.c b/src/mnode/src/mnodeMnode.c
index 205bfda4b9..8e3ad0a248 100644
--- a/src/mnode/src/mnodeMnode.c
+++ b/src/mnode/src/mnodeMnode.c
@@ -123,7 +123,7 @@ static int32_t mnodeMnodeActionRestored() {
       pMnode->role = TAOS_SYNC_ROLE_MASTER;
       mnodeDecMnodeRef(pMnode);
     }
-    sdbFreeIter(pIter);
+    mnodeCancelGetNextMnode(pIter);
   }
 
   mnodeUpdateMnodeEpSet();
@@ -161,6 +161,7 @@ int32_t mnodeInitMnodes() {
 
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_MNODE, mnodeGetMnodeMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_MNODE, mnodeRetrieveMnodes);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_MNODE, mnodeCancelGetNextMnode);
 
   mDebug("table:mnodes table is created");
   return TSDB_CODE_SUCCESS;
@@ -192,6 +193,10 @@ void *mnodeGetNextMnode(void *pIter, SMnodeObj **pMnode) {
   return sdbFetchRow(tsMnodeSdb, pIter, (void **)pMnode); 
 }
 
+void mnodeCancelGetNextMnode(void *pIter) {
+  sdbFreeIter(tsMnodeSdb, pIter);
+}
+
 void mnodeUpdateMnodeEpSet() {
   mInfo("update mnodes epSet, numOfEps:%d ", mnodeGetMnodesNum());
 
@@ -239,8 +244,6 @@ void mnodeUpdateMnodeEpSet() {
   tsMnodeEpSetForShell.numOfEps = index;
   tsMnodeEpSetForPeer.numOfEps = index;
 
-  sdbFreeIter(pIter);
-
   mnodeMnodeUnLock();
 }
 
diff --git a/src/mnode/src/mnodeProfile.c b/src/mnode/src/mnodeProfile.c
index 12ac64854c..8467adfc17 100644
--- a/src/mnode/src/mnodeProfile.c
+++ b/src/mnode/src/mnodeProfile.c
@@ -42,6 +42,7 @@ static int32_t mnodeGetQueryMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pC
 static int32_t mnodeRetrieveQueries(SShowObj *pShow, char *data, int32_t rows, void *pConn);
 static int32_t mnodeGetConnsMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pConn);
 static int32_t mnodeRetrieveConns(SShowObj *pShow, char *data, int32_t rows, void *pConn);
+static void    mnodeCancelGetNextConn(void *pIter);
 static int32_t mnodeGetStreamMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pConn);
 static int32_t mnodeRetrieveStreams(SShowObj *pShow, char *data, int32_t rows, void *pConn);
 static void    mnodeFreeConn(void *data);
@@ -52,10 +53,13 @@ static int32_t mnodeProcessKillConnectionMsg(SMnodeMsg *pMsg);
 int32_t mnodeInitProfile() {
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_QUERIES, mnodeGetQueryMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_QUERIES, mnodeRetrieveQueries);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_QUERIES, mnodeCancelGetNextConn);
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_CONNS, mnodeGetConnsMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_CONNS, mnodeRetrieveConns);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_CONNS, mnodeCancelGetNextConn);
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_STREAMS, mnodeGetStreamMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_STREAMS, mnodeRetrieveStreams);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_STREAMS, mnodeCancelGetNextConn);
 
   mnodeAddWriteMsgHandle(TSDB_MSG_TYPE_CM_KILL_QUERY, mnodeProcessKillQueryMsg);
   mnodeAddWriteMsgHandle(TSDB_MSG_TYPE_CM_KILL_STREAM, mnodeProcessKillStreamMsg);
@@ -137,21 +141,15 @@ static void mnodeFreeConn(void *data) {
   mDebug("connId:%d, is destroyed", pConn->connId);
 }
 
-static void *mnodeGetNextConn(SHashMutableIterator *pIter, SConnObj **pConn) {
+static void *mnodeGetNextConn(void *pIter, SConnObj **pConn) {
   *pConn = NULL;
 
-  if (pIter == NULL) {
-    pIter = taosHashCreateIter(tsMnodeConnCache->pHashTable);
-  }
+  pIter = taosHashIterate(tsMnodeConnCache->pHashTable, pIter);
+  if (pIter == NULL) return NULL;
 
-  if (!taosHashIterNext(pIter)) {
-    taosHashDestroyIter(pIter);
-    return NULL;
-  }
-
-  SCacheDataNode **pNode = taosHashIterGet(pIter);
+  SCacheDataNode **pNode = pIter;
   if (pNode == NULL || *pNode == NULL) {
-    taosHashDestroyIter(pIter);
+    taosHashCancelIterate(tsMnodeConnCache->pHashTable, pIter);
     return NULL;
   }
 
@@ -159,6 +157,10 @@ static void *mnodeGetNextConn(SHashMutableIterator *pIter, SConnObj **pConn) {
   return pIter;
 }
 
+static void mnodeCancelGetNextConn(void *pIter) {
+  taosHashCancelIterate(tsMnodeConnCache->pHashTable, pIter);
+}
+
 static int32_t mnodeGetConnsMeta(STableMetaMsg *pMeta, SShowObj *pShow, void *pConn) {
   SUserObj *pUser = mnodeGetUserFromConn(pConn);
   if (pUser == NULL) return 0;
diff --git a/src/mnode/src/mnodeSdb.c b/src/mnode/src/mnodeSdb.c
index 1728bb7e3b..575845b4f2 100644
--- a/src/mnode/src/mnodeSdb.c
+++ b/src/mnode/src/mnodeSdb.c
@@ -325,7 +325,6 @@ void sdbUpdateSync(void *pMnodes) {
       mnodeDecDnodeRef(pDnode);
       mnodeDecMnodeRef(pMnode);
     }
-    sdbFreeIter(pIter);
     syncCfg.replica = index;
     mDebug("vgId:1, mnodes info not input, use infos in sdb, numOfMnodes:%d", syncCfg.replica);
   } else {
@@ -756,24 +755,17 @@ int32_t sdbUpdateRow(SSdbRow *pRow) {
   }
 }
 
-void *sdbFetchRow(void *tparam, void *pNode, void **ppRow) {
+void *sdbFetchRow(void *tparam, void *pIter, void **ppRow) {
   SSdbTable *pTable = tparam;
   *ppRow = NULL;
   if (pTable == NULL) return NULL;
 
-  SHashMutableIterator *pIter = pNode;
-  if (pIter == NULL) {
-    pIter = taosHashCreateIter(pTable->iHandle);
-  }
+  pIter = taosHashIterate(pTable->iHandle, pIter);
+  if (pIter == NULL) return NULL;
 
-  if (!taosHashIterNext(pIter)) {
-    taosHashDestroyIter(pIter);
-    return NULL;
-  }
-
-  void **ppMetaRow = taosHashIterGet(pIter);
+  void **ppMetaRow = pIter;
   if (ppMetaRow == NULL) {
-    taosHashDestroyIter(pIter);
+    taosHashCancelIterate(pTable->iHandle, pIter);
     return NULL;
   }
 
@@ -783,10 +775,11 @@ void *sdbFetchRow(void *tparam, void *pNode, void **ppRow) {
   return pIter;
 }
 
-void sdbFreeIter(void *pIter) {
-  if (pIter != NULL) {
-    taosHashDestroyIter(pIter);
-  }
+void sdbFreeIter(void *tparam, void *pIter) {
+  SSdbTable *pTable = tparam;
+  if (pTable == NULL || pIter == NULL) return;
+
+  taosHashCancelIterate(pTable->iHandle, pIter);
 }
 
 void *sdbOpenTable(SSdbTableDesc *pDesc) {
@@ -827,9 +820,10 @@ void sdbCloseTable(void *handle) {
   tsSdbMgmt.numOfTables--;
   tsSdbMgmt.tableList[pTable->id] = NULL;
 
-  SHashMutableIterator *pIter = taosHashCreateIter(pTable->iHandle);
-  while (taosHashIterNext(pIter)) {
-    void **ppRow = taosHashIterGet(pIter);
+  void *pIter = taosHashIterate(pTable->iHandle, NULL);
+  while (pIter) {
+    void **ppRow = pIter;
+    pIter = taosHashIterate(pTable->iHandle, pIter);
     if (ppRow == NULL) continue;
 
     SSdbRow row = {
@@ -840,7 +834,7 @@ void sdbCloseTable(void *handle) {
     (*pTable->fpDestroy)(&row);
   }
 
-  taosHashDestroyIter(pIter);
+  taosHashCancelIterate(pTable->iHandle, pIter);
   taosHashCleanup(pTable->iHandle);
   pthread_mutex_destroy(&pTable->mutex);
 
diff --git a/src/mnode/src/mnodeShow.c b/src/mnode/src/mnodeShow.c
index 0d53fa9617..2621441cb5 100644
--- a/src/mnode/src/mnodeShow.c
+++ b/src/mnode/src/mnodeShow.c
@@ -57,6 +57,7 @@ static void *tsMnodeShowCache = NULL;
 static int32_t tsShowObjIndex = 0;
 static SShowMetaFp     tsMnodeShowMetaFp[TSDB_MGMT_TABLE_MAX]     = {0};
 static SShowRetrieveFp tsMnodeShowRetrieveFp[TSDB_MGMT_TABLE_MAX] = {0};
+static SShowFreeIterFp tsMnodeShowFreeIterFp[TSDB_MGMT_TABLE_MAX] = {0};
 
 int32_t mnodeInitShow() {
   mnodeAddReadMsgHandle(TSDB_MSG_TYPE_CM_SHOW, mnodeProcessShowMsg);
@@ -85,6 +86,10 @@ void mnodeAddShowRetrieveHandle(uint8_t msgType, SShowRetrieveFp fp) {
   tsMnodeShowRetrieveFp[msgType] = fp;
 }
 
+void mnodeAddShowFreeIterHandle(uint8_t msgType, SShowFreeIterFp fp) {
+  tsMnodeShowFreeIterFp[msgType] = fp;
+}
+
 static char *mnodeGetShowType(int32_t showType) {
   switch (showType) {
     case TSDB_MGMT_TABLE_ACCT:    return "show accounts";
@@ -412,7 +417,9 @@ static void* mnodePutShowObj(SShowObj *pShow) {
 
 static void mnodeFreeShowObj(void *data) {
   SShowObj *pShow = *(SShowObj **)data;
-  sdbFreeIter(pShow->pIter);
+  if (tsMnodeShowFreeIterFp[pShow->type] != NULL && pShow->pIter != NULL) {
+    (*tsMnodeShowFreeIterFp[pShow->type])(pShow->pIter);
+  }
 
   mDebug("%p, show is destroyed, data:%p index:%d", pShow, data, pShow->index);
   tfree(pShow);
diff --git a/src/mnode/src/mnodeTable.c b/src/mnode/src/mnodeTable.c
index 4d5f0808f5..8b07f73c65 100644
--- a/src/mnode/src/mnodeTable.c
+++ b/src/mnode/src/mnodeTable.c
@@ -342,8 +342,7 @@ static int32_t mnodeChildTableActionRestored() {
     mnodeDecTableRef(pTable);
   }
 
-  sdbFreeIter(pIter);
-
+  mnodeCancelGetNextChildTable(pIter);
   return 0;
 }
 
@@ -602,10 +601,13 @@ int32_t mnodeInitTables() {
 
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_TABLE, mnodeGetShowTableMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_TABLE, mnodeRetrieveShowTables);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_TABLE, mnodeCancelGetNextChildTable);
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_METRIC, mnodeGetShowSuperTableMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_METRIC, mnodeRetrieveShowSuperTables);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_METRIC, mnodeCancelGetNextSuperTable);
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_STREAMTABLES, mnodeGetStreamTableMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_STREAMTABLES, mnodeRetrieveStreamTables);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_STREAMTABLES, mnodeCancelGetNextChildTable);
 
   return TSDB_CODE_SUCCESS;
 }
@@ -626,14 +628,12 @@ static void *mnodeGetSuperTableByUid(uint64_t uid) {
     pIter = mnodeGetNextSuperTable(pIter, &pStable);
     if (pStable == NULL) break;
     if (pStable->uid == uid) {
-      sdbFreeIter(pIter);
+      mnodeCancelGetNextSuperTable(pIter);
       return pStable;
     }
     mnodeDecTableRef(pStable);
   }
 
-  sdbFreeIter(pIter);
-
   return NULL;
 }
 
@@ -655,10 +655,18 @@ void *mnodeGetNextChildTable(void *pIter, SCTableObj **pTable) {
   return sdbFetchRow(tsChildTableSdb, pIter, (void **)pTable);
 }
 
+void mnodeCancelGetNextChildTable(void *pIter) {
+  sdbFreeIter(tsChildTableSdb, pIter);
+}
+
 void *mnodeGetNextSuperTable(void *pIter, SSTableObj **pTable) {
   return sdbFetchRow(tsSuperTableSdb, pIter, (void **)pTable);
 }
 
+void mnodeCancelGetNextSuperTable(void *pIter) {
+  sdbFreeIter(tsSuperTableSdb, pIter);
+}
+
 void mnodeIncTableRef(void *p1) {
   STableObj *pTable = (STableObj *)p1;
   if (pTable->type == TSDB_SUPER_TABLE) {
@@ -914,10 +922,10 @@ static int32_t mnodeProcessDropSuperTableMsg(SMnodeMsg *pMsg) {
 
   SSTableObj *pStable = (SSTableObj *)pMsg->pTable;
    if (pStable->vgHash != NULL /*pStable->numOfTables != 0*/) {
-    SHashMutableIterator *pIter = taosHashCreateIter(pStable->vgHash);
-    while (taosHashIterNext(pIter)) {
-      int32_t *pVgId = taosHashIterGet(pIter);
+    int32_t *pVgId = taosHashIterate(pStable->vgHash, NULL);
+    while (pVgId) {
       SVgObj *pVgroup = mnodeGetVgroup(*pVgId);
+      pVgId = taosHashIterate(pStable->vgHash, pVgId);
       if (pVgroup == NULL) break;
 
       SDropSTableMsg *pDrop = rpcMallocCont(sizeof(SDropSTableMsg));
@@ -933,7 +941,8 @@ static int32_t mnodeProcessDropSuperTableMsg(SMnodeMsg *pMsg) {
       dnodeSendMsgToDnode(&epSet, &rpcMsg);
       mnodeDecVgroupRef(pVgroup);
     }
-    taosHashDestroyIter(pIter);
+
+    taosHashCancelIterate(pStable->vgHash, pVgId);
 
     mnodeDropAllChildTablesInStable(pStable);
   } 
@@ -1430,8 +1439,6 @@ void mnodeDropAllSuperTables(SDbObj *pDropDb) {
     mnodeDecTableRef(pTable);
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("db:%s, all super tables:%d is dropped from sdb", pDropDb->name, numOfTables);
 }
 
@@ -1523,11 +1530,11 @@ static int32_t mnodeProcessSuperTableVgroupMsg(SMnodeMsg *pMsg) {
     } else {
       SVgroupsMsg *pVgroupMsg = (SVgroupsMsg *)msg;
 
-      SHashMutableIterator *pIter = taosHashCreateIter(pTable->vgHash);
-      int32_t               vgSize = 0;
-      while (taosHashIterNext(pIter)) {
-        int32_t *pVgId = taosHashIterGet(pIter);
-        SVgObj * pVgroup = mnodeGetVgroup(*pVgId);
+      int32_t *pVgId = taosHashIterate(pTable->vgHash, NULL);
+      int32_t  vgSize = 0;
+      while (pVgId) {
+        SVgObj *pVgroup = mnodeGetVgroup(*pVgId);
+        pVgId = taosHashIterate(pTable->vgHash, pVgId);
         if (pVgroup == NULL) continue;
 
         pVgroupMsg->vgroups[vgSize].vgId = htonl(pVgroup->vgId);
@@ -1547,7 +1554,7 @@ static int32_t mnodeProcessSuperTableVgroupMsg(SMnodeMsg *pMsg) {
         mnodeDecVgroupRef(pVgroup);
       }
 
-      taosHashDestroyIter(pIter);
+      taosHashCancelIterate(pTable->vgHash, pVgId);
       mnodeDecTableRef(pTable);
 
       pVgroupMsg->numOfVgroups = htonl(vgSize);
@@ -2230,8 +2237,6 @@ void mnodeDropAllChildTablesInVgroups(SVgObj *pVgroup) {
     mnodeDecTableRef(pTable);
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("vgId:%d, all child tables is dropped from sdb", pVgroup->vgId);
 }
 
@@ -2263,8 +2268,6 @@ void mnodeDropAllChildTables(SDbObj *pDropDb) {
     mnodeDecTableRef(pTable);
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("db:%s, all child tables:%d is dropped from sdb", pDropDb->name, numOfTables);
 }
 
@@ -2293,8 +2296,6 @@ static void mnodeDropAllChildTablesInStable(SSTableObj *pStable) {
     mnodeDecTableRef(pTable);
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("stable:%s, all child tables:%d is dropped from sdb", pStable->info.tableId, numOfTables);
 }
 
diff --git a/src/mnode/src/mnodeUser.c b/src/mnode/src/mnodeUser.c
index dc76d92eb8..aee167631f 100644
--- a/src/mnode/src/mnodeUser.c
+++ b/src/mnode/src/mnodeUser.c
@@ -123,7 +123,6 @@ static void mnodePrintUserAuth() {
   }
 
   fflush(fp);
-  sdbFreeIter(pIter);
   fclose(fp);
 }
 
@@ -177,6 +176,8 @@ int32_t mnodeInitUsers() {
   mnodeAddWriteMsgHandle(TSDB_MSG_TYPE_CM_DROP_USER, mnodeProcessDropUserMsg);
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_USER, mnodeGetUserMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_USER, mnodeRetrieveUsers);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_USER, mnodeCancelGetNextUser);
+
   mnodeAddPeerMsgHandle(TSDB_MSG_TYPE_DM_AUTH, mnodeProcessAuthMsg);
    
   mDebug("table:%s, hash is created", desc.name);
@@ -196,6 +197,10 @@ void *mnodeGetNextUser(void *pIter, SUserObj **pUser) {
   return sdbFetchRow(tsUserSdb, pIter, (void **)pUser); 
 }
 
+void mnodeCancelGetNextUser(void *pIter) {
+ sdbFreeIter(tsUserSdb, pIter);
+}
+
 void mnodeIncUserRef(SUserObj *pUser) { 
   return sdbIncRef(tsUserSdb, pUser); 
 }
@@ -574,8 +579,6 @@ void mnodeDropAllUsers(SAcctObj *pAcct)  {
     mnodeDecUserRef(pUser);
   }
 
-  sdbFreeIter(pIter);
-
   mDebug("acct:%s, all users:%d is dropped from sdb", pAcct->user, numOfUsers);
 }
 
diff --git a/src/mnode/src/mnodeVgroup.c b/src/mnode/src/mnodeVgroup.c
index f9a49e5ec2..a8343083aa 100644
--- a/src/mnode/src/mnodeVgroup.c
+++ b/src/mnode/src/mnodeVgroup.c
@@ -230,6 +230,7 @@ int32_t mnodeInitVgroups() {
 
   mnodeAddShowMetaHandle(TSDB_MGMT_TABLE_VGROUP, mnodeGetVgroupMeta);
   mnodeAddShowRetrieveHandle(TSDB_MGMT_TABLE_VGROUP, mnodeRetrieveVgroups);
+  mnodeAddShowFreeIterHandle(TSDB_MGMT_TABLE_VGROUP, mnodeCancelGetNextVgroup);
   mnodeAddPeerRspHandle(TSDB_MSG_TYPE_MD_CREATE_VNODE_RSP, mnodeProcessCreateVnodeRsp);
   mnodeAddPeerRspHandle(TSDB_MSG_TYPE_MD_ALTER_VNODE_RSP, mnodeProcessAlterVnodeRsp);
   mnodeAddPeerRspHandle(TSDB_MSG_TYPE_MD_DROP_VNODE_RSP, mnodeProcessDropVnodeRsp);
@@ -304,7 +305,7 @@ void mnodeCheckUnCreatedVgroup(SDnodeObj *pDnode, SVnodeLoad *pVloads, int32_t o
     mnodeDecVgroupRef(pVgroup);
   }
 
-  sdbFreeIter(pIter);
+  mnodeCancelGetNextVgroup(pIter);
 }
 
 void mnodeUpdateVgroupStatus(SVgObj *pVgroup, SDnodeObj *pDnode, SVnodeLoad *pVload) {
@@ -491,6 +492,10 @@ void *mnodeGetNextVgroup(void *pIter, SVgObj **pVgroup) {
   return sdbFetchRow(tsVgroupSdb, pIter, (void **)pVgroup); 
 }
 
+void mnodeCancelGetNextVgroup(void *pIter) {
+  sdbFreeIter(tsVgroupSdb, pIter);
+}
+
 static int32_t mnodeCreateVgroupFp(SMnodeMsg *pMsg) {
   SVgObj *pVgroup = pMsg->pVgroup;
   SDbObj *pDb = pMsg->pDb;
@@ -1095,8 +1100,6 @@ void mnodeDropAllDnodeVgroups(SDnodeObj *pDropDnode) {
     mnodeDecVgroupRef(pVgroup);
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("dnode:%d, all vgroups:%d is dropped from sdb", pDropDnode->dnodeId, numOfVgroups);
 }
 
@@ -1118,8 +1121,6 @@ void mnodeUpdateAllDbVgroups(SDbObj *pAlterDb) {
     mnodeDecVgroupRef(pVgroup);
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("db:%s, all vgroups is updated in sdb", pAlterDb->name);
 }
 #endif
@@ -1147,8 +1148,6 @@ void mnodeDropAllDbVgroups(SDbObj *pDropDb) {
     mnodeDecVgroupRef(pVgroup);
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("db:%s, all vgroups:%d is dropped from sdb", pDropDb->name, numOfVgroups);
 }
 
@@ -1170,7 +1169,5 @@ void mnodeSendDropAllDbVgroupsMsg(SDbObj *pDropDb) {
     numOfVgroups++;
   }
 
-  sdbFreeIter(pIter);
-
   mInfo("db:%s, all vgroups:%d drop msg is sent to dnode", pDropDb->name, numOfVgroups);
 }
diff --git a/src/vnode/src/vnodeMain.c b/src/vnode/src/vnodeMain.c
index 339391369f..74df989090 100644
--- a/src/vnode/src/vnodeMain.c
+++ b/src/vnode/src/vnodeMain.c
@@ -542,10 +542,11 @@ void vnodeBuildStatusMsg(void *param) {
 
   void *pIter = taosHashIterate(tsVnodesHash, NULL);
   while (pIter) {
-    SVnodeObj **pVnode = pIter; 
-    if (*pVnode) { 
-    vnodeBuildVloadMsg(*pVnode, pStatus);
+    SVnodeObj **pVnode = pIter;
+    if (*pVnode) {
+      vnodeBuildVloadMsg(*pVnode, pStatus);
     }
+    pIter = taosHashIterate(tsVnodesHash, pIter);
   }
 }
 
diff --git a/tests/script/basicSuite.sim b/tests/script/basicSuite.sim
index 61a9d68d26..5e22e02297 100644
--- a/tests/script/basicSuite.sim
+++ b/tests/script/basicSuite.sim
@@ -14,7 +14,6 @@ run general/table/vgroup.sim
 run general/user/authority.sim
 run general/vector/metrics_mix.sim
 run general/vector/table_field.sim
-run general/user/authority.sim
 run general/tag/set.sim
 run general/table/delete_writing.sim
 run general/stable/disk.sim

From d0e85228401fe967cb99dc06acc8a65bef573615 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 11:12:58 +0800
Subject: [PATCH 05/41] [TD-2175]<fix>: fix the error in result field name and
 nchar column length

---
 src/client/src/tscSql.c | 11 ++++++++++-
 src/query/inc/sql.y     |  8 ++++----
 src/query/src/sql.c     | 11 +++++------
 3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/src/client/src/tscSql.c b/src/client/src/tscSql.c
index 020305a0a8..de01776472 100644
--- a/src/client/src/tscSql.c
+++ b/src/client/src/tscSql.c
@@ -420,7 +420,16 @@ TAOS_FIELD *taos_fetch_fields(TAOS_RES *res) {
     for(int32_t i = 0; i < pFieldInfo->numOfOutput; ++i) {
       SInternalField* pField = tscFieldInfoGetInternalField(pFieldInfo, i);
       if (pField->visible) {
-        f[j++] = pField->field;
+        f[j] = pField->field;
+
+        // revise the length for binary and nchar fields
+        if (f[j].type == TSDB_DATA_TYPE_BINARY) {
+          f[j].bytes -= VARSTR_HEADER_SIZE;
+        } else if (f[j].type == TSDB_DATA_TYPE_NCHAR) {
+          f[j].bytes = (f[j].bytes - VARSTR_HEADER_SIZE)/TSDB_NCHAR_SIZE;
+        }
+
+        j += 1;
       }
     }
 
diff --git a/src/query/inc/sql.y b/src/query/inc/sql.y
index 09b1e1592a..e2b3bb6cbf 100644
--- a/src/query/inc/sql.y
+++ b/src/query/inc/sql.y
@@ -556,11 +556,11 @@ having_opt(A) ::= HAVING expr(X).   {A = X;}
 //limit-offset subclause
 %type limit_opt {SLimitVal}
 limit_opt(A) ::= .                     {A.limit = -1; A.offset = 0;}
-limit_opt(A) ::= LIMIT signed(X).      {printf("aa1, %d\n", X); A.limit = X;  A.offset = 0;}
+limit_opt(A) ::= LIMIT signed(X).      {A.limit = X;  A.offset = 0;}
 limit_opt(A) ::= LIMIT signed(X) OFFSET signed(Y).
-                                       {printf("aa2\n, %d\n", X); A.limit = X;  A.offset = Y;}
+                                       { A.limit = X;  A.offset = Y;}
 limit_opt(A) ::= LIMIT signed(X) COMMA signed(Y).
-                                       {printf("aa3\n, %d\n", X); A.limit = Y;  A.offset = X;}
+                                       { A.limit = Y;  A.offset = X;}
 
 %type slimit_opt {SLimitVal}
 slimit_opt(A) ::= .                    {A.limit = -1; A.offset = 0;}
@@ -581,7 +581,7 @@ where_opt(A) ::= WHERE expr(X).       {A = X;}
 %type expr {tSQLExpr*}
 %destructor expr {tSQLExprDestroy($$);}
 
-expr(A) ::= LP expr(X) RP.       {A = X; }
+expr(A) ::= LP(X) expr(Y) RP(Z).       {A = Y; A->token.z = X.z; A->token.n = (Z.z - X.z + 1);}
 
 expr(A) ::= ID(X).               {A = tSQLExprIdValueCreate(&X, TK_ID);}
 expr(A) ::= ID(X) DOT ID(Y).     {X.n += (1+Y.n); A = tSQLExprIdValueCreate(&X, TK_ID);}
diff --git a/src/query/src/sql.c b/src/query/src/sql.c
index da2c56ee9e..d4e2b7f5f4 100644
--- a/src/query/src/sql.c
+++ b/src/query/src/sql.c
@@ -2628,16 +2628,14 @@ static void yy_reduce(
 {yymsp[1].minor.yy216.limit = -1; yymsp[1].minor.yy216.offset = 0;}
         break;
       case 177: /* limit_opt ::= LIMIT signed */
+      case 181: /* slimit_opt ::= SLIMIT signed */ yytestcase(yyruleno==181);
 {yymsp[-1].minor.yy216.limit = yymsp[0].minor.yy207;  yymsp[-1].minor.yy216.offset = 0;}
         break;
       case 178: /* limit_opt ::= LIMIT signed OFFSET signed */
-{yymsp[-3].minor.yy216.limit = yymsp[-2].minor.yy207;  yymsp[-3].minor.yy216.offset = yymsp[0].minor.yy207;}
+{ yymsp[-3].minor.yy216.limit = yymsp[-2].minor.yy207;  yymsp[-3].minor.yy216.offset = yymsp[0].minor.yy207;}
         break;
       case 179: /* limit_opt ::= LIMIT signed COMMA signed */
-{yymsp[-3].minor.yy216.limit = yymsp[0].minor.yy207;  yymsp[-3].minor.yy216.offset = yymsp[-2].minor.yy207;}
-        break;
-      case 181: /* slimit_opt ::= SLIMIT signed */
-{yymsp[-1].minor.yy216.limit = yymsp[0].minor.yy207;  yymsp[-1].minor.yy216.offset = 0;}
+{ yymsp[-3].minor.yy216.limit = yymsp[0].minor.yy207;  yymsp[-3].minor.yy216.offset = yymsp[-2].minor.yy207;}
         break;
       case 182: /* slimit_opt ::= SLIMIT signed SOFFSET signed */
 {yymsp[-3].minor.yy216.limit = yymsp[-2].minor.yy207;  yymsp[-3].minor.yy216.offset = yymsp[0].minor.yy207;}
@@ -2646,7 +2644,8 @@ static void yy_reduce(
 {yymsp[-3].minor.yy216.limit = yymsp[0].minor.yy207;  yymsp[-3].minor.yy216.offset = yymsp[-2].minor.yy207;}
         break;
       case 186: /* expr ::= LP expr RP */
-{yymsp[-2].minor.yy64 = yymsp[-1].minor.yy64; }
+{yylhsminor.yy64 = yymsp[-1].minor.yy64; yylhsminor.yy64->token.z = yymsp[-2].minor.yy0.z; yylhsminor.yy64->token.n = (yymsp[0].minor.yy0.z - yymsp[-2].minor.yy0.z + 1);}
+  yymsp[-2].minor.yy64 = yylhsminor.yy64;
         break;
       case 187: /* expr ::= ID */
 {yylhsminor.yy64 = tSQLExprIdValueCreate(&yymsp[0].minor.yy0, TK_ID);}

From 98ba80a993556d12fcc8cffa26d70c711445bc23 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 11:13:46 +0800
Subject: [PATCH 06/41] [TD-225] refactor codes.

---
 src/query/inc/qUtil.h      |  2 ++
 src/query/src/qExecutor.c  | 54 ++++++++++++++++++++++++--------------
 src/query/src/qResultbuf.c |  2 +-
 src/query/src/qUtil.c      | 51 +++++++++++++++++------------------
 4 files changed, 63 insertions(+), 46 deletions(-)

diff --git a/src/query/inc/qUtil.h b/src/query/inc/qUtil.h
index 4cd0e60ebe..b2c4b6e2ec 100644
--- a/src/query/inc/qUtil.h
+++ b/src/query/inc/qUtil.h
@@ -80,5 +80,7 @@ void* destroyResultRowPool(SResultRowPool* p);
 int32_t getNumOfAllocatedResultRows(SResultRowPool* p);
 int32_t getNumOfUsedResultRows(SResultRowPool* p);
 
+uint64_t getResultInfoUId(SQueryRuntimeEnv* pRuntimeEnv);
+
 
 #endif  // TDENGINE_QUERYUTIL_H
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index d0874c36bc..c44d65e373 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -186,7 +186,7 @@ static void setExecParams(SQuery *pQuery, SQLFunctionCtx *pCtx, void* inputData,
 
 static void initCtxOutputBuf(SQueryRuntimeEnv *pRuntimeEnv);
 static void destroyTableQueryInfoImpl(STableQueryInfo *pTableQueryInfo);
-static void resetCtxOutputBuf(SQueryRuntimeEnv *pRuntimeEnv);
+static void resetDefaultResInfoOutputBuf(SQueryRuntimeEnv *pRuntimeEnv);
 static bool hasMainOutput(SQuery *pQuery);
 static void buildTagQueryResult(SQInfo *pQInfo);
 
@@ -283,8 +283,8 @@ void updateNumOfResult(SQueryRuntimeEnv *pRuntimeEnv, int32_t numOfRes) {
   }
 }
 
-static UNUSED_FUNC int32_t getGroupResultId(int32_t groupIndex) {
-  int32_t base = 20000000;
+static int32_t getMergeResultGroupId(int32_t groupIndex) {
+  int32_t base = 50000000;
   return base + (groupIndex * 10000);
 }
 
@@ -1115,7 +1115,7 @@ static int32_t setGroupResultOutputBuf(SQueryRuntimeEnv *pRuntimeEnv, char *pDat
 
   SDiskbasedResultBuf *pResultBuf = pRuntimeEnv->pResultBuf;
 
-  // not assign result buffer yet, add new result buffer
+  // not assign result buffer yet, add new result buffer, TODO remove it
   char* d = pData;
   int16_t len = bytes;
   if (type == TSDB_DATA_TYPE_BINARY||type == TSDB_DATA_TYPE_NCHAR) {
@@ -1128,7 +1128,7 @@ static int32_t setGroupResultOutputBuf(SQueryRuntimeEnv *pRuntimeEnv, char *pDat
     longjmp(pRuntimeEnv->env, TSDB_CODE_QRY_APP_ERROR);
   }
 
-  uint64_t uid = groupIndex; // uid is always set to be 0.
+  uint64_t uid = groupIndex;
   SResultRow *pResultRow = doPrepareResultRowFromKey(pRuntimeEnv, &pRuntimeEnv->windowResInfo, d, len, true, uid);
   if (pResultRow == NULL) {
     return -1;
@@ -1714,7 +1714,7 @@ static int32_t setupQueryRuntimeEnv(SQueryRuntimeEnv *pRuntimeEnv, int16_t order
   // if it is group by normal column, do not set output buffer, the output buffer is pResult
   // fixed output query/multi-output query for normal table
   if (!pRuntimeEnv->groupbyNormalCol && !pRuntimeEnv->stableQuery && !QUERY_IS_INTERVAL_QUERY(pRuntimeEnv->pQuery)) {
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
   }
 
   if (setCtxTagColumnInfo(pRuntimeEnv, pRuntimeEnv->pCtx) != TSDB_CODE_SUCCESS) {
@@ -2936,10 +2936,24 @@ void copyResToQueryResultBuf(SQInfo *pQInfo, SQuery *pQuery) {
   assert(size == pGroupResInfo->numOfDataPages);
 
   bool done = false;
+
+  //TODO add API for release none-dirty pages
+//  SPageInfo* prev = NULL;
+
   for (int32_t j = pGroupResInfo->pageId; j < size; ++j) {
     SPageInfo* pi = *(SPageInfo**) taosArrayGet(list, j);
     tFilePage* pData = getResBufPage(pResultBuf, pi->pageId);
 
+    // release previous buffer pages
+//    if (prev == NULL) {
+//      prev = pi;
+//    } else {
+//      if (prev->pageId != pi->pageId) {
+//        releaseResBufPageInfo(pResultBuf, prev);
+//        prev = pi;
+//      }
+//    }
+
     assert(pData->num > 0 && pData->num <= pRuntimeEnv->numOfRowsPerPage && pGroupResInfo->rowId < pData->num);
     int32_t numOfRes = (int32_t)(pData->num - pGroupResInfo->rowId);
 
@@ -3058,7 +3072,7 @@ int32_t mergeIntoGroupResultImpl(SQInfo *pQInfo, SArray *pGroup) {
   SResultRow* pRow = getNewResultRow(pRuntimeEnv->pool);
   resetMergeResultBuf(pRuntimeEnv, pRuntimeEnv->pCtx, pRow);
 
-  pQInfo->groupResInfo.groupId = getGroupResultId(pQInfo->groupIndex);
+  pQInfo->groupResInfo.groupId = getMergeResultGroupId(pQInfo->groupIndex);
 
   // todo add windowRes iterator
   int64_t lastTimestamp = -1;
@@ -3339,12 +3353,12 @@ int32_t initResultRow(SResultRow *pResultRow) {
   return TSDB_CODE_SUCCESS;
 }
 
-void resetCtxOutputBuf(SQueryRuntimeEnv *pRuntimeEnv) {
+void resetDefaultResInfoOutputBuf(SQueryRuntimeEnv *pRuntimeEnv) {
   SQuery *pQuery = pRuntimeEnv->pQuery;
 
-  int32_t groupIndex = 0;
-  int32_t uid = 0;
-  SResultRow* pRow = doPrepareResultRowFromKey(pRuntimeEnv, &pRuntimeEnv->windowResInfo, (char *)&groupIndex, sizeof(groupIndex), true, uid);
+  int32_t tid = 0;
+  int64_t uid = getResultInfoUId(pRuntimeEnv);
+  SResultRow* pRow = doPrepareResultRowFromKey(pRuntimeEnv, &pRuntimeEnv->windowResInfo, (char *)&tid, sizeof(tid), true, uid);
 
   for (int32_t i = 0; i < pQuery->numOfOutput; ++i) {
     SQLFunctionCtx *pCtx = &pRuntimeEnv->pCtx[i];
@@ -3427,7 +3441,7 @@ void skipResults(SQueryRuntimeEnv *pRuntimeEnv) {
     pQuery->limit.offset -= pQuery->rec.rows;
     pQuery->rec.rows = 0;
 
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
 
     // clear the buffer full flag if exists
     CLEAR_QUERY_STATUS(pQuery, QUERY_RESBUF_FULL);
@@ -3792,7 +3806,7 @@ void setExecutionContext(SQInfo *pQInfo, int32_t groupIndex, TSKEY nextKey) {
     return;
   }
 
-  uint64_t uid = 0; // uid is always set to be 0
+  uint64_t uid = getResultInfoUId(pRuntimeEnv);
   SResultRow *pResultRow = doPrepareResultRowFromKey(pRuntimeEnv, pWindowResInfo, (char *)&groupIndex,
       sizeof(groupIndex), true, uid);
   if (pResultRow == NULL) {
@@ -4629,10 +4643,10 @@ int32_t doInitQInfo(SQInfo *pQInfo, STSBuf *pTsBuf, void *tsdb, int32_t vgId, bo
   int32_t ps = DEFAULT_PAGE_SIZE;
   int32_t rowsize = 0;
   getIntermediateBufInfo(pRuntimeEnv, &ps, &rowsize);
-  int32_t TWOMB = 1024*1024*2;
+  int32_t TENMB = 1024*1024*10;
 
   if (isSTableQuery && !onlyQueryTags(pRuntimeEnv->pQuery)) {
-    code = createDiskbasedResultBuffer(&pRuntimeEnv->pResultBuf, rowsize, ps, TWOMB, pQInfo);
+    code = createDiskbasedResultBuffer(&pRuntimeEnv->pResultBuf, rowsize, ps, TENMB, pQInfo);
     if (code != TSDB_CODE_SUCCESS) {
       return code;
     }
@@ -4660,7 +4674,7 @@ int32_t doInitQInfo(SQInfo *pQInfo, STSBuf *pTsBuf, void *tsdb, int32_t vgId, bo
   } else if (pRuntimeEnv->groupbyNormalCol || QUERY_IS_INTERVAL_QUERY(pQuery) || (!isSTableQuery)) {
     int32_t numOfResultRows = getInitialPageNum(pQInfo);
     getIntermediateBufInfo(pRuntimeEnv, &ps, &rowsize);
-    code = createDiskbasedResultBuffer(&pRuntimeEnv->pResultBuf, rowsize, ps, TWOMB, pQInfo);
+    code = createDiskbasedResultBuffer(&pRuntimeEnv->pResultBuf, rowsize, ps, TENMB, pQInfo);
     if (code != TSDB_CODE_SUCCESS) {
       return code;
     }
@@ -4930,7 +4944,7 @@ static void sequentialTableProcess(SQInfo *pQInfo) {
   size_t numOfGroups = GET_NUM_OF_TABLEGROUP(pQInfo);
 
   if (isPointInterpoQuery(pQuery)) {
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
     assert(pQuery->limit.offset == 0 && pQuery->limit.limit != 0);
 
     while (pQInfo->groupIndex < numOfGroups) {
@@ -5096,7 +5110,7 @@ static void sequentialTableProcess(SQInfo *pQInfo) {
       return;
     }
 
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
     resetTimeWindowInfo(pRuntimeEnv, &pRuntimeEnv->windowResInfo);
 
     SArray *group = GET_TABLEGROUP(pQInfo, 0);
@@ -5456,7 +5470,7 @@ static void tableMultiOutputProcess(SQInfo *pQInfo, STableQueryInfo* pTableInfo)
 
   // for ts_comp query, re-initialized is not allowed
   if (!isTSCompQuery(pQuery)) {
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
   }
 
   // skip blocks without load the actual data block from file if no filter condition present
@@ -5486,7 +5500,7 @@ static void tableMultiOutputProcess(SQInfo *pQInfo, STableQueryInfo* pTableInfo)
     qDebug("QInfo:%p skip current result, offset:%" PRId64 ", next qrange:%" PRId64 "-%" PRId64,
            pQInfo, pQuery->limit.offset, pQuery->current->lastKey, pQuery->current->win.ekey);
 
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
   }
 
   limitResults(pRuntimeEnv);
diff --git a/src/query/src/qResultbuf.c b/src/query/src/qResultbuf.c
index c5ba551f20..67cb7af074 100644
--- a/src/query/src/qResultbuf.c
+++ b/src/query/src/qResultbuf.c
@@ -407,7 +407,7 @@ void destroyResultBuf(SDiskbasedResultBuf* pResultBuf) {
   }
 
   if (pResultBuf->file != NULL) {
-    qDebug("QInfo:%p res output buffer closed, total:%.2f Kb, inmem size:%.2f Kb, file size:%.2f",
+    qDebug("QInfo:%p res output buffer closed, total:%.2f Kb, inmem size:%.2f Kb, file size:%.2f Kb",
         pResultBuf->handle, pResultBuf->totalBufSize/1024.0, listNEles(pResultBuf->lruList) * pResultBuf->pageSize / 1024.0,
         pResultBuf->fileSize/1024.0);
 
diff --git a/src/query/src/qUtil.c b/src/query/src/qUtil.c
index c5317226c7..650b886c36 100644
--- a/src/query/src/qUtil.c
+++ b/src/query/src/qUtil.c
@@ -20,6 +20,18 @@
 #include "qExecutor.h"
 #include "qUtil.h"
 
+static int32_t getResultRowKeyInfo(SResultRow* pResult, int16_t type, char** key, int16_t* bytes) {
+  if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
+    *key   = varDataVal(pResult->key);
+    *bytes = varDataLen(pResult->key);
+  } else {
+    *key = (char*) &pResult->win.skey;
+    *bytes = tDataTypeDesc[type].nSize;
+  }
+
+  return 0;
+}
+
 int32_t getOutputInterResultBufSize(SQuery* pQuery) {
   int32_t size = 0;
 
@@ -94,12 +106,8 @@ void clearFirstNWindowRes(SQueryRuntimeEnv *pRuntimeEnv, int32_t num) {
   int32_t numOfClosed = numOfClosedTimeWindow(pWindowResInfo);
   assert(num >= 0 && num <= numOfClosed);
 
-  int16_t  type = pWindowResInfo->type;
-  STableId* id  = TSDB_TABLEID(pRuntimeEnv->pQuery->current->pTable); // uid is always set to be 0.
-  int64_t uid = id->uid;
-  if (pRuntimeEnv->groupbyNormalCol) {
-    uid = 0;
-  }
+  int16_t type = pWindowResInfo->type;
+  int64_t uid = getResultInfoUId(pRuntimeEnv);
 
   char    *key  = NULL;
   int16_t  bytes = -1;
@@ -107,16 +115,7 @@ void clearFirstNWindowRes(SQueryRuntimeEnv *pRuntimeEnv, int32_t num) {
   for (int32_t i = 0; i < num; ++i) {
     SResultRow *pResult = pWindowResInfo->pResult[i];
     if (pResult->closed) {  // remove the window slot from hash table
-
-      // todo refactor
-      if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
-        key   = varDataVal(pResult->key);
-        bytes = varDataLen(pResult->key);
-      } else {
-        key = (char*) &pResult->win.skey;
-        bytes = tDataTypeDesc[pWindowResInfo->type].nSize;
-      }
-
+      getResultRowKeyInfo(pResult, type, &key, &bytes);
       SET_RES_WINDOW_KEY(pRuntimeEnv->keyBuf, key, bytes, uid);
       taosHashRemove(pRuntimeEnv->pResultRowHashTable, (const char *)pRuntimeEnv->keyBuf, GET_RES_WINDOW_KEY_LEN(bytes));
     } else {
@@ -141,16 +140,9 @@ void clearFirstNWindowRes(SQueryRuntimeEnv *pRuntimeEnv, int32_t num) {
 
   for (int32_t k = 0; k < pWindowResInfo->size; ++k) {
     SResultRow *pResult = pWindowResInfo->pResult[k];
-
-    if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
-      key = varDataVal(pResult->key);
-      bytes = varDataLen(pResult->key);
-    } else {
-      key = (char*) &pResult->win.skey;
-      bytes = tDataTypeDesc[pWindowResInfo->type].nSize;
-    }
-
+    getResultRowKeyInfo(pResult, type, &key, &bytes);
     SET_RES_WINDOW_KEY(pRuntimeEnv->keyBuf, key, bytes, uid);
+
     int32_t *p = (int32_t *)taosHashGet(pRuntimeEnv->pResultRowHashTable, (const char *)pRuntimeEnv->keyBuf, GET_RES_WINDOW_KEY_LEN(bytes));
     assert(p != NULL); 
 
@@ -379,3 +371,12 @@ void* destroyResultRowPool(SResultRowPool* p) {
   tfree(p);
   return NULL;
 }
+
+uint64_t getResultInfoUId(SQueryRuntimeEnv* pRuntimeEnv) {
+  if (!pRuntimeEnv->stableQuery) {
+    return 0;  // for simple table query, the uid is always set to be 0;
+  }
+
+  STableId* id = TSDB_TABLEID(pRuntimeEnv->pQuery->current);
+  return id->uid;
+}
\ No newline at end of file

From 227823762cac5dbfa333308d023c6c0a80463e5c Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 11:14:27 +0800
Subject: [PATCH 07/41] [TD-2175] add test cases.

---
 src/client/tests/resultFieldTest.cpp | 138 +++++++++++++++++++++++++++
 1 file changed, 138 insertions(+)
 create mode 100644 src/client/tests/resultFieldTest.cpp

diff --git a/src/client/tests/resultFieldTest.cpp b/src/client/tests/resultFieldTest.cpp
new file mode 100644
index 0000000000..c917f0ebaf
--- /dev/null
+++ b/src/client/tests/resultFieldTest.cpp
@@ -0,0 +1,138 @@
+#include <gtest/gtest.h>
+#include <iostream>
+
+#include "taos.h"
+
+namespace {
+static int64_t start_ts = 1433955661000;
+}
+/* test parse time function */
+TEST(testCase, result_field_test) {
+  taos_options(TSDB_OPTION_CONFIGDIR, "~/first/cfg");
+  taos_init();
+
+  TAOS* conn = taos_connect("ubuntu", "root", "taosdata", 0, 0);
+  if (conn == NULL) {
+    printf("Failed to connect to DB, reason:%s", taos_errstr(conn));
+    exit(-1);
+  }
+
+  TAOS_RES* res = taos_query(conn, "create database if not exists test");
+  ASSERT_EQ(taos_errno(res), 0);
+  taos_free_result(res);
+
+  res = taos_query(conn, "use test");
+  ASSERT_EQ(taos_errno(res), 0);
+  taos_free_result(res);
+
+  res = taos_query(conn, "create table if not exists t1(ts timestamp, k int, a binary(11), b nchar(4))");
+  ASSERT_EQ(taos_errno(res), 0);
+  taos_free_result(res);
+
+  char sql[512] = {0};
+  sprintf(sql, "insert into t1 values(%ld, 99, 'abc', 'test')", start_ts);
+
+  res = taos_query(conn, sql);
+  ASSERT_EQ(taos_errno(res), 0);
+  taos_free_result(res);
+
+  res = taos_query(conn, "select count(*), spread(ts)/(1000 * 3600 * 24), first(a), last(b) from t1");
+  ASSERT_EQ(taos_num_fields(res), 4);
+
+  TAOS_FIELD* fields = taos_fetch_fields(res);
+  ASSERT_EQ(fields[0].bytes, 8);
+  ASSERT_EQ(fields[0].type, TSDB_DATA_TYPE_BIGINT);
+  ASSERT_STREQ(fields[0].name, "count(*)");
+
+  ASSERT_EQ(fields[1].bytes, 8);
+  ASSERT_EQ(fields[1].type, TSDB_DATA_TYPE_DOUBLE);
+  ASSERT_STREQ(fields[1].name, "spread(ts)/(1000 * 3600 * 24)");
+
+  ASSERT_EQ(fields[2].bytes, 11);
+  ASSERT_EQ(fields[2].type, TSDB_DATA_TYPE_BINARY);
+  ASSERT_STREQ(fields[2].name, "first(a)");
+
+  ASSERT_EQ(fields[3].bytes, 4);
+  ASSERT_EQ(fields[3].type, TSDB_DATA_TYPE_NCHAR);
+  ASSERT_STREQ(fields[3].name, "last(b)");
+
+  taos_free_result(res);
+
+  res = taos_query(conn, "select last_row(*) from t1");
+  ASSERT_EQ(taos_num_fields(res), 4);
+
+  fields = taos_fetch_fields(res);
+  ASSERT_EQ(fields[0].bytes, 8);
+  ASSERT_EQ(fields[0].type, TSDB_DATA_TYPE_TIMESTAMP);
+  ASSERT_STREQ(fields[0].name, "last_row(ts)");
+
+  ASSERT_EQ(fields[1].bytes, 4);
+  ASSERT_EQ(fields[1].type, TSDB_DATA_TYPE_INT);
+  ASSERT_STREQ(fields[1].name, "last_row(k)");
+
+  ASSERT_EQ(fields[2].bytes, 11);
+  ASSERT_EQ(fields[2].type, TSDB_DATA_TYPE_BINARY);
+  ASSERT_STREQ(fields[2].name, "last_row(a)");
+
+  ASSERT_EQ(fields[3].bytes, 4);
+  ASSERT_EQ(fields[3].type, TSDB_DATA_TYPE_NCHAR);
+  ASSERT_STREQ(fields[3].name, "last_row(b)");
+
+  taos_free_result(res);
+  res = taos_query(conn, "select first(*), last(*) from t1");
+  ASSERT_EQ(taos_num_fields(res), 8);
+
+  fields = taos_fetch_fields(res);
+  ASSERT_EQ(fields[0].bytes, 8);
+  ASSERT_EQ(fields[0].type, TSDB_DATA_TYPE_TIMESTAMP);
+  ASSERT_STREQ(fields[0].name, "first(ts)");
+
+  ASSERT_EQ(fields[1].bytes, 4);
+  ASSERT_EQ(fields[1].type, TSDB_DATA_TYPE_INT);
+  ASSERT_STREQ(fields[1].name, "first(k)");
+
+  ASSERT_EQ(fields[2].bytes, 11);
+  ASSERT_EQ(fields[2].type, TSDB_DATA_TYPE_BINARY);
+  ASSERT_STREQ(fields[2].name, "first(a)");
+
+  ASSERT_EQ(fields[3].bytes, 4);
+  ASSERT_EQ(fields[3].type, TSDB_DATA_TYPE_NCHAR);
+  ASSERT_STREQ(fields[3].name, "first(b)");
+
+  taos_free_result(res);
+
+  res = taos_query(conn, "select first(ts, a, k, k, b, b, ts) from t1");
+  ASSERT_EQ(taos_num_fields(res), 7);
+
+  fields = taos_fetch_fields(res);
+  ASSERT_EQ(fields[0].bytes, 8);
+  ASSERT_EQ(fields[0].type, TSDB_DATA_TYPE_TIMESTAMP);
+  ASSERT_STREQ(fields[0].name, "first(ts)");
+
+  ASSERT_EQ(fields[1].bytes, 11);
+  ASSERT_EQ(fields[1].type, TSDB_DATA_TYPE_BINARY);
+  ASSERT_STREQ(fields[1].name, "first(a)");
+
+  ASSERT_EQ(fields[2].bytes, 4);
+  ASSERT_EQ(fields[2].type, TSDB_DATA_TYPE_INT);
+  ASSERT_STREQ(fields[2].name, "first(k)");
+
+  ASSERT_EQ(fields[3].bytes, 4);
+  ASSERT_EQ(fields[3].type, TSDB_DATA_TYPE_INT);
+  ASSERT_STREQ(fields[3].name, "first(k)");
+
+  ASSERT_EQ(fields[4].bytes, 4);
+  ASSERT_EQ(fields[4].type, TSDB_DATA_TYPE_NCHAR);
+  ASSERT_STREQ(fields[4].name, "first(b)");
+
+  ASSERT_EQ(fields[5].bytes, 4);
+  ASSERT_EQ(fields[5].type, TSDB_DATA_TYPE_NCHAR);
+  ASSERT_STREQ(fields[5].name, "first(b)");
+
+  ASSERT_EQ(fields[6].bytes, 8);
+  ASSERT_EQ(fields[6].type, TSDB_DATA_TYPE_TIMESTAMP);
+  ASSERT_STREQ(fields[6].name, "first(ts)");
+
+  taos_free_result(res);
+  taos_close(conn);
+}

From 6a837620f0539d30ebb6affe5a7fa89f3848db93 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 11:15:59 +0800
Subject: [PATCH 08/41] [TD-225] update the sim script.

---
 .../parser/col_arithmetic_operation.sim       | 100 +++-----
 .../general/parser/col_arithmetic_query.sim   | 240 ++++++++++++++++++
 2 files changed, 269 insertions(+), 71 deletions(-)
 create mode 100644 tests/script/general/parser/col_arithmetic_query.sim

diff --git a/tests/script/general/parser/col_arithmetic_operation.sim b/tests/script/general/parser/col_arithmetic_operation.sim
index d5ba57e6c7..c05229ab65 100644
--- a/tests/script/general/parser/col_arithmetic_operation.sim
+++ b/tests/script/general/parser/col_arithmetic_operation.sim
@@ -5,6 +5,7 @@ system sh/cfg.sh -n dnode1 -c walLevel -v 0
 system sh/exec.sh -n dnode1 -s start
 sleep 500
 sql connect
+#========================================= setup environment ================================
 
 $dbPrefix = ca_db
 $tbPrefix = ca_tb
@@ -52,44 +53,39 @@ while $i < $halfTbNum
   $i = $i + 1
 endw 
 
-##### select from table
-$tb = $tbPrefix . 0
-## TBASE-344
-sql select c1*2 from $tb
-if $rows != $rowNum then
-  return -1
-endi
-if $data00 != 0.000000000 then
-  return -1
-endi
-if $data10 != 2.000000000 then
-  return -1
-endi
-if $data20 != 4.000000000 then
-  return -1
-endi
-if $data90 != 18.000000000 then
-  return -1
-endi
+#=================================== above are setup test environment =============================
+run general/parser/col_arithmetic_query.sim
 
-sql select c4*1+1/2 from $tb
-if $rows != $rowNum then
-  return -1
-endi
-if $data00 != 0.500000000 then
-  return -1
-endi
-if $data10 != 1.500000000 then
-  return -1
-endi
-if $data90 != 9.500000000 then
-  return -1
-endi
+#======================================= all in files query =======================================
+print ================== restart server to commit data into disk
+system sh/exec.sh -n dnode1 -s stop -x SIGINT
+sleep 3000
+system sh/exec.sh -n dnode1 -s start
 
-#### illegal operations
+print ================== server restart completed
+sql connect
+sleep 500
+
+run general/parser/col_arithmetic_query.sim
+
+# ================================================================================================
+
+print ====================> crash
+# sql select spread(ts )/(1000*3600*24) from ca_stb0 interval(1y)
+
+
+sql_error select first(c1, c2) - last(c1, c2) from stb interval(1y)
+sql_error select first(ts) - last(ts) from stb interval(1y)
+sql_error select top(c1, 2) - last(c1) from stb;
+sql_error select stddev(c1) - last(c1) from stb;
+sql_error select diff(c1) - last(c1) from stb;
+sql_error select first(c7) - last(c7) from stb;
+sql_error select first(c8) - last(c8) from stb;
+sql_error select first(c9) - last(c9) from stb;
 sql_error select max(c2*2) from $tb
 sql_error select max(c1-c2) from $tb
 
+#========================================regression test cases====================================
 print =====================> td-1764
 sql select sum(c1)/count(*), sum(c1) as b, count(*) as b from $stb interval(1y)
 if $rows != 1 then
@@ -108,42 +104,4 @@ if $data02 != 225000 then
   return -1
 endi
 
-sql select first(c1) - last(c1), first(c1) as b, last(c1) as b, min(c1) - max(c1), spread(c1) from ca_stb0 interval(1y)
-if $rows != 1 then
-  return -1
-endi
-
-if $data00 != @18-01-01 00:00:00.000@ then
-  return -1
-endi
-
-if $data01 != -9.000000000 then
-  return -1
-endi
-
-if $data02 != 0 then
-  return -1
-endi
-
-if $data03 != 9 then
-  return -1
-endi
-
-if $data04 != -9.000000000 then
-  return -1
-endi
-
-if $data05 != 9.000000000 then
-  return -1
-endi
-
-sql_error select first(c1, c2) - last(c1, c2) from stb interval(1y)
-sql_error select first(ts) - last(ts) from stb interval(1y)
-sql_error select top(c1, 2) - last(c1) from stb;
-sql_error select stddev(c1) - last(c1) from stb;
-sql_error select diff(c1) - last(c1) from stb;
-sql_error select first(c7) - last(c7) from stb;
-sql_error select first(c8) - last(c8) from stb;
-sql_error select first(c9) - last(c9) from stb;
-
 system sh/exec.sh -n dnode1 -s stop -x SIGINT
\ No newline at end of file
diff --git a/tests/script/general/parser/col_arithmetic_query.sim b/tests/script/general/parser/col_arithmetic_query.sim
new file mode 100644
index 0000000000..95258168ef
--- /dev/null
+++ b/tests/script/general/parser/col_arithmetic_query.sim
@@ -0,0 +1,240 @@
+# ======================================= query test cases ========================================
+# select from table
+
+$tb = $tbPrefix . 0
+## TBASE-344
+sql select c1*2 from $tb
+if $rows != $rowNum then
+  return -1
+endi
+if $data00 != 0.000000000 then
+  return -1
+endi
+if $data10 != 2.000000000 then
+  return -1
+endi
+if $data20 != 4.000000000 then
+  return -1
+endi
+if $data90 != 18.000000000 then
+  return -1
+endi
+
+# asc/desc order [d.2]
+sql select c1 *( 2 / 3 ), c1/c1 from $tb order by ts asc;
+sql select (c1 * 2) % 7.9 from $tb order by ts desc;
+
+sql select c1 * c2 /4 from $tb where ts <  and ts >
+
+# no result return [d.3]
+sql select c1 * 91- 7 from $tb where ts<1537146000000
+if $rows != 0 then
+  return -1
+endi
+
+# no result return [d.3]
+sql select c2 - c2 from $tb where ts>xxx
+if $rows != 0 then
+  return -1
+endi
+
+# single row result aggregation [d.4]
+# not available
+
+# error cases
+sql_error select first(c1,c2) - last(c1,c2) from $tb
+
+# multi row result aggregation [d.4]
+sql select top(c1, 1) - bottom(c1, 1) from $tb
+sql select top(c1, 99) - bottom(c1, 99) from $tb
+
+# all data types [d.6]
+sql select c2-c1, c3/c2, c4*c3, c5%c4, c6+99%22 from $tb
+
+
+
+# error case, ts/bool/binary/nchar not support arithmetic expression
+sql_error select ts+ts from $tb
+sql_error select ts+22 from $tb
+sql_error select c7*12 from $tb
+sql_error select c8/55 from $tb
+sql_error select c9+c8 from $tb
+sql_error select c7-c8, c9-c8 from $tb
+sql_error select ts-c9 from $tb
+sql_error select c8+c7, c9+c9+c8+c7/c6 from $tb
+sql_error select c1/0, c2/0, c3/0.0 from $tb
+sql_error select c1/0.00000000001 from $tb
+
+# arithmetic expression in join [d.7]
+
+
+# arithmetic expression in union [d.8]
+
+
+# arithmetic expression in group by [d.9]
+# in group by tag
+# not support for normal table
+sql_error select c5*99 from $tb group by t1
+
+# in group by column
+sql_error select c6-(c6+c3)*12 from $tb group by c3;
+
+
+# limit offset [d.10]
+sql select c6 - c6 + 12 from $tb limit 12 offset 99;
+sql select c4 / 99.123 from $tb limit 1 offset 9999;
+
+# slimit/soffset not support for normal table query. [d.11]
+sql_error select sum(c1) from $tb slimit 1 soffset 19;
+
+# fill [d.12]
+sql_error select c2-c2, c3-c4, c5%c6 from $tb fill(value, 12);
+
+# constant column. [d.13]
+
+
+# column value filter [d.14]
+
+
+# tag filter(not support for normal table). [d.15]
+sql_error select c2+99 from $tb where t1=12;
+
+# multi-field output [d.16]
+sql select count(*), sum(c1)*avg(c2), avg(c3)*count(c3), sum(c3), sum(c4), first(c7), last(c8), first(c9), first(c7), last(c8) from $tb
+
+sql select c4*1+1/2 from $tb
+if $rows != $rowNum then
+  return -1
+endi
+if $data00 != 0.500000000 then
+  return -1
+endi
+if $data10 != 1.500000000 then
+  return -1
+endi
+if $data90 != 9.500000000 then
+  return -1
+endi
+
+# interval query [d.17]
+sql_error select c2*c2, c3-c3, c4+9 from $tb interval(1s)
+sql_error select c7-c9 from $tb interval(2y)
+
+# aggregation query [d.18]
+# see test cases below
+
+# first/last query  [d.19]
+# see test cases below
+
+# multiple retrieve [d.20]
+sql select c2-c2 from $tb;
+
+#======================================= aggregation function arithmetic query cases ================
+# asc/desc order [d.2]
+sql select first(c1) * ( 2 / 3 ) from $stb order by ts asc;
+sql select (count(c1) * 2) % 7.9 from $stb order by ts desc;
+
+# all possible function in the arithmetic expressioin
+sql select min(c1) * max(c2) /4, sum(c1) * percentile(c2, 20), apercentile(c4, 33) + 52/9, spread(c5)/min(c2), xxxx, from $stb where ts <  and ts >
+
+# no result return [d.3]
+sql select first(c1) * 91 - 7, last(c3) from $stb where ts < 1537146000000
+if $rows != 0 then
+  return -1
+endi
+
+# no result return [d.3]
+sql select sum(c2) - avg(c2) from $tb where ts>xxx
+if $rows != 0 then
+  return -1
+endi
+
+# single row result aggregation [d.4]
+sql select
+
+# error cases
+sql_error select first(c1, c2) - last(c1, c2) from $tb
+
+# multi row result aggregation [d.4]
+sql select top(c1, 1) - bottom(c1, 1) from $tb
+sql select top(c1, 99) - bottom(c1, 99) from $tb
+
+# all data types [d.6]
+sql select c2-c1, c3/c2, c4*c3, c5%c4, c6+99%22 from $tb
+
+# error case, ts/bool/binary/nchar not support arithmetic expression
+sql_error select ts+ts from $tb
+sql_error select ts+22 from $tb
+sql_error select c7*12 from $tb
+sql_error select c8/55 from $tb
+sql_error select c9+c8 from $tb
+
+# arithmetic expression in join [d.7]
+
+
+# arithmetic expression in union [d.8]
+
+
+# arithmetic expression in group by [d.9]
+# in group by tag
+# not support for normal table
+sql_error select c5*99 from $tb group by t1
+
+# in group by column
+sql_error select c6-c6+c3*12 from $tb group by c3;
+
+sql select first(c6) - last(c6) *12 / count(*) from $tb group by c3;
+
+# limit offset [d.10]
+sql select c6-c6+12 from $tb limit 12 offset 99;
+sql select c4/99.123 from $tb limit 1 offset 9999;
+
+# slimit/soffset not suport for normal table query. [d.11]
+sql_error select sum(c1) from $tb slimit 1 soffset 19;
+
+# fill [d.12]
+sql_error select c2-c2, c3-c4, c5%c6 from $tb fill(value, 12);
+
+# constant column. [d.13]
+
+
+# column value filter [d.14]
+
+
+# tag filter(not support for normal table). [d.15]
+sql_error select c2+99 from $tb where t1=12;
+
+# multi-field output [d.16]
+sql select count(*), sum(c1)*avg(c2), avg(c3)*count(c3), sum(c3), sum(c4), first(c7), last(c8), first(c9), first(c7), last(c8) from $tb
+
+sql select c4*1+1/2 from $tb
+if $rows != $rowNum then
+  return -1
+endi
+if $data00 != 0.500000000 then
+  return -1
+endi
+if $data10 != 1.500000000 then
+  return -1
+endi
+if $data90 != 9.500000000 then
+  return -1
+endi
+
+# interval query [d.17]
+sql_error select c2*c2, c3-c3, c4+9 from $tb interval(1s)
+sql_error select c7-c9 from $tb interval(2y)
+
+# aggregation query [d.18]
+# see test cases below
+
+# first/last query  [d.19]
+# see test cases below
+
+# multiple retrieve [d.20]
+sql select c2-c2 from $tb;
+
+
+sql select first(c1)-last(c1), spread(c2), max(c3) - min(c3), avg(c4)*count(c4) from $tb
+
+

From 5894dded1ddf64561f6e991b8f92469bde27650a Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 12:47:34 +0800
Subject: [PATCH 09/41] [TD-2169]<fix>: fix memory leak in handing the group by
 binary|nchar type data.

---
 src/query/inc/qUtil.h |  2 +-
 src/query/src/qUtil.c | 19 +++++++++++++++----
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/src/query/inc/qUtil.h b/src/query/inc/qUtil.h
index b2c4b6e2ec..62bf245a2b 100644
--- a/src/query/inc/qUtil.h
+++ b/src/query/inc/qUtil.h
@@ -26,7 +26,7 @@
 
 int32_t getOutputInterResultBufSize(SQuery* pQuery);
 
-void clearResultRow(SQueryRuntimeEnv* pRuntimeEnv, SResultRow* pRow);
+void clearResultRow(SQueryRuntimeEnv* pRuntimeEnv, SResultRow* pRow, int16_t type);
 void copyResultRow(SQueryRuntimeEnv* pRuntimeEnv, SResultRow* dst, const SResultRow* src);
 SResultRowCellInfo* getResultCell(SQueryRuntimeEnv* pRuntimeEnv, const SResultRow* pRow, int32_t index);
 
diff --git a/src/query/src/qUtil.c b/src/query/src/qUtil.c
index 650b886c36..4b8d7ea930 100644
--- a/src/query/src/qUtil.c
+++ b/src/query/src/qUtil.c
@@ -68,6 +68,12 @@ void cleanupTimeWindowInfo(SWindowResInfo *pWindowResInfo) {
     assert(pWindowResInfo->pResult == NULL);
     return;
   }
+
+  if (pWindowResInfo->type == TSDB_DATA_TYPE_BINARY || pWindowResInfo->type == TSDB_DATA_TYPE_NCHAR) {
+    for(int32_t i = 0; i < pWindowResInfo->size; ++i) {
+      tfree(pWindowResInfo->pResult[i]->key);
+    }
+  }
   
   tfree(pWindowResInfo->pResult);
 }
@@ -81,7 +87,7 @@ void resetTimeWindowInfo(SQueryRuntimeEnv *pRuntimeEnv, SWindowResInfo *pWindowR
 
   for (int32_t i = 0; i < pWindowResInfo->size; ++i) {
     SResultRow *pWindowRes = pWindowResInfo->pResult[i];
-    clearResultRow(pRuntimeEnv, pWindowRes);
+    clearResultRow(pRuntimeEnv, pWindowRes, pWindowResInfo->type);
 
     int32_t groupIndex = 0;
     int64_t uid = 0;
@@ -133,7 +139,7 @@ void clearFirstNWindowRes(SQueryRuntimeEnv *pRuntimeEnv, int32_t num) {
   // move the unclosed window in the front of the window list
   for (int32_t k = remain; k < pWindowResInfo->size; ++k) {
     SResultRow *pWindowRes = pWindowResInfo->pResult[k];
-    clearResultRow(pRuntimeEnv, pWindowRes);
+    clearResultRow(pRuntimeEnv, pWindowRes, pWindowResInfo->type);
   }
   
   pWindowResInfo->size = remain;
@@ -229,7 +235,7 @@ void closeTimeWindow(SWindowResInfo *pWindowResInfo, int32_t slot) {
   getResultRow(pWindowResInfo, slot)->closed = true;
 }
 
-void clearResultRow(SQueryRuntimeEnv *pRuntimeEnv, SResultRow *pWindowRes) {
+void clearResultRow(SQueryRuntimeEnv *pRuntimeEnv, SResultRow *pWindowRes, int16_t type) {
   if (pWindowRes == NULL) {
     return;
   }
@@ -253,7 +259,12 @@ void clearResultRow(SQueryRuntimeEnv *pRuntimeEnv, SResultRow *pWindowRes) {
   pWindowRes->pageId = -1;
   pWindowRes->rowId = -1;
   pWindowRes->closed = false;
-  pWindowRes->win = TSWINDOW_INITIALIZER;
+
+  if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
+    tfree(pWindowRes->key);
+  } else {
+    pWindowRes->win = TSWINDOW_INITIALIZER;
+  }
 }
 
 /**

From f55fce821764f91f36e2fb8c23706bead039f8bf Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 14:01:10 +0800
Subject: [PATCH 10/41] [TD-2163]<enhance>: add the version check for query
 message.

---
 src/client/src/tscServer.c | 3 ++-
 src/inc/taosmsg.h          | 2 ++
 src/query/src/qExecutor.c  | 4 ++++
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index cbc5604a27..eaa00f290b 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -669,6 +669,7 @@ int tscBuildQueryMsg(SSqlObj *pSql, SSqlInfo *pInfo) {
   }
 
   SQueryTableMsg *pQueryMsg = (SQueryTableMsg *)pCmd->payload;
+  tstrncpy(pQueryMsg->version, version, tListLen(pQueryMsg->version));
 
   int32_t numOfTags = (int32_t)taosArrayGetSize(pTableMetaInfo->tagColList);
   
@@ -693,8 +694,8 @@ int tscBuildQueryMsg(SSqlObj *pSql, SSqlInfo *pInfo) {
   pQueryMsg->interval.slidingUnit  = pQueryInfo->interval.slidingUnit;
   pQueryMsg->interval.offsetUnit   = pQueryInfo->interval.offsetUnit;
   pQueryMsg->numOfGroupCols = htons(pQueryInfo->groupbyExpr.numOfGroupCols);
-  pQueryMsg->numOfTags      = htonl(numOfTags);
   pQueryMsg->tagNameRelType = htons(pQueryInfo->tagCond.relType);
+  pQueryMsg->numOfTags      = htonl(numOfTags);
   pQueryMsg->queryType      = htonl(pQueryInfo->type);
   
   size_t numOfOutput = tscSqlExprNumOfExprs(pQueryInfo);
diff --git a/src/inc/taosmsg.h b/src/inc/taosmsg.h
index 681fa44929..b77db69c46 100644
--- a/src/inc/taosmsg.h
+++ b/src/inc/taosmsg.h
@@ -464,6 +464,8 @@ typedef struct STimeWindow {
 
 typedef struct {
   SMsgHead    head;
+  char        version[TSDB_VERSION_LEN];
+
   STimeWindow window;
   int32_t     numOfTables;
   int16_t     order;
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index c44d65e373..630a469dd7 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -5825,6 +5825,10 @@ static int32_t convertQueryMsg(SQueryTableMsg *pQueryMsg, SArray **pTableIdList,
                                char **tagCond, char** tbnameCond, SColIndex **groupbyCols, SColumnInfo** tagCols) {
   int32_t code = TSDB_CODE_SUCCESS;
 
+  if (taosCheckVersion(pQueryMsg->version, version, 3) != 0) {
+    return TSDB_CODE_QRY_INVALID_MSG;
+  }
+
   pQueryMsg->numOfTables = htonl(pQueryMsg->numOfTables);
 
   pQueryMsg->window.skey = htobe64(pQueryMsg->window.skey);

From 7df48991217b8f487cfdc30eade6a1413e919b48 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 16:27:04 +0800
Subject: [PATCH 11/41] [TD-2180]<fix>: fix coverity issues.

---
 src/client/src/tscPrepare.c                   | 72 +++++++++----------
 src/client/src/tscSQLParser.c                 | 13 +---
 src/client/src/tscServer.c                    |  6 +-
 src/client/src/tscUtil.c                      |  7 +-
 src/common/src/tvariant.c                     |  4 +-
 src/query/src/qExecutor.c                     |  2 +-
 src/query/src/qParserImpl.c                   |  3 +-
 src/query/src/qResultbuf.c                    |  7 +-
 src/query/src/qTsbuf.c                        |  4 +-
 .../parser/col_arithmetic_operation.sim       |  1 -
 10 files changed, 59 insertions(+), 60 deletions(-)

diff --git a/src/client/src/tscPrepare.c b/src/client/src/tscPrepare.c
index 68f2ecbf0e..30e0729427 100644
--- a/src/client/src/tscPrepare.c
+++ b/src/client/src/tscPrepare.c
@@ -258,11 +258,7 @@ static char* normalStmtBuildSql(STscStmt* stmt) {
 
 static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
   if (bind->is_null != NULL && *(bind->is_null)) {
-    if (param->type == TSDB_DATA_TYPE_BINARY || param->type == TSDB_DATA_TYPE_NCHAR) {
-      setVardataNull(data + param->offset, param->type);
-    } else {
-      setNull(data + param->offset, param->type, param->bytes);
-    }
+    setNull(data + param->offset, param->type, param->bytes);
     return TSDB_CODE_SUCCESS;
   }
 
@@ -312,13 +308,13 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
               break;
             }
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_FLOAT:
           case TSDB_DATA_TYPE_DOUBLE:
           case TSDB_DATA_TYPE_TIMESTAMP:
           default: {
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
         }
         memcpy(data + param->offset, &u.v1, sizeof(u.v1));
         return TSDB_CODE_SUCCESS;
@@ -336,40 +332,40 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
             u.v1 = (int8_t)v;
             if (v >= SCHAR_MIN && v <= SCHAR_MAX) break;
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_INT: {
             int32_t v = *(int32_t*)bind->buffer;
             u.v1 = (int8_t)v;
             if (v >= SCHAR_MIN && v <= SCHAR_MAX) break;
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_BIGINT: {
             int64_t v = *(int64_t*)bind->buffer;
             u.v1 = (int8_t)v;
             if (v >= SCHAR_MIN && v <= SCHAR_MAX) break;
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_BINARY:
           case TSDB_DATA_TYPE_NCHAR: {
             int64_t v;
-            int n,r;
+            int     n, r;
             r = sscanf((const char*)bind->buffer, "%" PRId64 "%n", &v, &n);
-            if (r==1 && n==strlen((const char*)bind->buffer)) {
+            if (r == 1 && n == strlen((const char*)bind->buffer)) {
               u.v1 = (int8_t)v;
               if (v >= SCHAR_MIN && v <= SCHAR_MAX) break;
             }
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_FLOAT:
           case TSDB_DATA_TYPE_DOUBLE:
           case TSDB_DATA_TYPE_TIMESTAMP:
           default: {
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
         }
         memcpy(data + param->offset, &u.v1, sizeof(u.v1));
         return TSDB_CODE_SUCCESS;
-			} break;
+      }
       case TSDB_DATA_TYPE_SMALLINT: {
         switch (bind->buffer_type) {
           case TSDB_DATA_TYPE_BOOL:
@@ -383,34 +379,34 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
             u.v2 = (int16_t)v;
             if (v >= SHRT_MIN && v <= SHRT_MAX) break;
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_BIGINT: {
             int64_t v = *(int64_t*)bind->buffer;
             u.v2 = (int16_t)v;
             if (v >= SHRT_MIN && v <= SHRT_MAX) break;
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_BINARY:
           case TSDB_DATA_TYPE_NCHAR: {
             int64_t v;
-            int n,r;
+            int     n, r;
             r = sscanf((const char*)bind->buffer, "%" PRId64 "%n", &v, &n);
-            if (r==1 && n==strlen((const char*)bind->buffer)) {
+            if (r == 1 && n == strlen((const char*)bind->buffer)) {
               u.v2 = (int16_t)v;
               if (v >= SHRT_MIN && v <= SHRT_MAX) break;
             }
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_FLOAT:
           case TSDB_DATA_TYPE_DOUBLE:
           case TSDB_DATA_TYPE_TIMESTAMP:
           default: {
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
         }
         memcpy(data + param->offset, &u.v2, sizeof(u.v2));
         return TSDB_CODE_SUCCESS;
-			} break;
+      }
       case TSDB_DATA_TYPE_INT: {
         switch (bind->buffer_type) {
           case TSDB_DATA_TYPE_BOOL:
@@ -514,17 +510,17 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
               break;
             }
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_FLOAT:
           case TSDB_DATA_TYPE_DOUBLE:
           case TSDB_DATA_TYPE_TIMESTAMP:
           default: {
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
         }
         memcpy(data + param->offset, &u.v8, sizeof(u.v8));
         return TSDB_CODE_SUCCESS;
-			} break;
+      }
       case TSDB_DATA_TYPE_DOUBLE: {
         switch (bind->buffer_type) {
           case TSDB_DATA_TYPE_BOOL:
@@ -556,15 +552,15 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
               break;
             }
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
           case TSDB_DATA_TYPE_TIMESTAMP:
           default: {
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
-        } break;
+          }
+        }
         memcpy(data + param->offset, &u.f8, sizeof(u.f8));
         return TSDB_CODE_SUCCESS;
-			} break;
+      }
       case TSDB_DATA_TYPE_TIMESTAMP: {
         switch (bind->buffer_type) {
           case TSDB_DATA_TYPE_TIMESTAMP: {
@@ -589,10 +585,10 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
           default: {
             return TSDB_CODE_TSC_INVALID_VALUE;
           } break;
-        } break;
+        };
         memcpy(data + param->offset, &u.v8, sizeof(u.v8));
         return TSDB_CODE_SUCCESS;
-			} break;
+			}
       case TSDB_DATA_TYPE_BINARY: {
         switch (bind->buffer_type) {
           case TSDB_DATA_TYPE_BINARY: {
@@ -602,7 +598,7 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
             short size = (short)*bind->length;
             STR_WITH_SIZE_TO_VARSTR(data + param->offset, bind->buffer, size);
             return TSDB_CODE_SUCCESS;
-          } break;
+          }
           case TSDB_DATA_TYPE_BOOL:
           case TSDB_DATA_TYPE_TINYINT:
           case TSDB_DATA_TYPE_SMALLINT:
@@ -614,9 +610,9 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
           case TSDB_DATA_TYPE_NCHAR:
           default: {
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
         }
-			} break;
+      }
       case TSDB_DATA_TYPE_NCHAR: {
         switch (bind->buffer_type) {
           case TSDB_DATA_TYPE_NCHAR: {
@@ -626,7 +622,7 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
             }
             varDataSetLen(data + param->offset, output);
             return TSDB_CODE_SUCCESS;
-          } break;
+          }
           case TSDB_DATA_TYPE_BOOL:
           case TSDB_DATA_TYPE_TINYINT:
           case TSDB_DATA_TYPE_SMALLINT:
@@ -638,12 +634,12 @@ static int doBindParam(char* data, SParamInfo* param, TAOS_BIND* bind) {
           case TSDB_DATA_TYPE_BINARY:
           default: {
             return TSDB_CODE_TSC_INVALID_VALUE;
-          } break;
+          }
         }
-			} break;
+      }
       default: {
         return TSDB_CODE_TSC_INVALID_VALUE;
-      } break;
+      }
     }
   }
 
diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index 15d2647c51..f859d2969e 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -80,7 +80,6 @@ static int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprLis
 static bool validateIpAddress(const char* ip, size_t size);
 static bool hasUnsupportFunctionsForSTableQuery(SSqlCmd* pCmd, SQueryInfo* pQueryInfo);
 static bool functionCompatibleCheck(SQueryInfo* pQueryInfo, bool joinQuery);
-static void setColumnOffsetValueInResultset(SQueryInfo* pQueryInfo);
 
 static int32_t parseGroupbyClause(SQueryInfo* pQueryInfo, SArray* pList, SSqlCmd* pCmd);
 
@@ -2951,14 +2950,6 @@ int32_t parseGroupbyClause(SQueryInfo* pQueryInfo, SArray* pList, SSqlCmd* pCmd)
   return TSDB_CODE_SUCCESS;
 }
 
-void setColumnOffsetValueInResultset(SQueryInfo* pQueryInfo) {
-  if (QUERY_IS_STABLE_QUERY(pQueryInfo->type)) {
-    tscFieldInfoUpdateOffset(pQueryInfo);
-  } else {
-    tscFieldInfoUpdateOffset(pQueryInfo);
-  }
-}
-
 static SColumnFilterInfo* addColumnFilterInfo(SColumn* pColumn) {
   if (pColumn == NULL) {
     return NULL;
@@ -3537,7 +3528,7 @@ static int32_t validateSQLExpr(SSqlCmd* pCmd, tSQLExpr* pExpr, SQueryInfo* pQuer
 
       if (i == 0) {
         id = p1->uid;
-      } else if (id != p1->uid){
+      } else if (id != p1->uid) {
         return TSDB_CODE_TSC_INVALID_SQL;
       }
     }
@@ -6531,7 +6522,7 @@ int32_t doCheckForQuery(SSqlObj* pSql, SQuerySQL* pQuerySql, int32_t index) {
     return code;
   }
 
-  setColumnOffsetValueInResultset(pQueryInfo);
+  tscFieldInfoUpdateOffset(pQueryInfo);
 
   /*
    * fill options are set at the end position, when all columns are set properly
diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index eaa00f290b..15859674ab 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -62,7 +62,7 @@ static void tscSetDnodeEpSet(SSqlObj* pSql, SVgroupInfo* pVgroupInfo) {
 
   pEpSet->numOfEps = pVgroupInfo->numOfEps;
   for(int32_t i = 0; i < pVgroupInfo->numOfEps; ++i) {
-    strcpy(pEpSet->fqdn[i], pVgroupInfo->epAddr[i].fqdn);
+    tstrncpy(pEpSet->fqdn[i], pVgroupInfo->epAddr[i].fqdn, tListLen(pEpSet->fqdn[i]));
     pEpSet->port[i] = pVgroupInfo->epAddr[i].port;
 
     if (!hasFqdn) {
@@ -2031,7 +2031,8 @@ static void createHBObj(STscObj* pObj) {
 
   SQueryInfo *pQueryInfo = tscGetQueryInfoDetailSafely(&pSql->cmd, 0);
   if (pQueryInfo == NULL) {
-    pSql->res.code = terrno;
+    terrno = TSDB_CODE_TSC_OUT_OF_MEMORY;
+    tfree(pSql);
     return;
   }
 
@@ -2039,6 +2040,7 @@ static void createHBObj(STscObj* pObj) {
 
   pSql->cmd.command = pQueryInfo->command;
   if (TSDB_CODE_SUCCESS != tscAllocPayload(&(pSql->cmd), TSDB_DEFAULT_PAYLOAD_SIZE)) {
+    terrno = TSDB_CODE_TSC_OUT_OF_MEMORY;
     tfree(pSql);
     return;
   }
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index 7a82bcaaab..a75f6d8296 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -451,14 +451,16 @@ void tscFreeRegisteredSqlObj(void *pSql) {
   STscObj* pTscObj = (*p)->pTscObj;
 
   assert((*p)->self != 0 && (*p)->self == (p));
+
+  SSqlObj* ptr = *p;
   tscFreeSqlObj(*p);
 
   int32_t ref = T_REF_DEC(pTscObj);
   assert(ref >= 0);
 
-  tscDebug("%p free sqlObj completed, tscObj:%p ref:%d", *p, pTscObj, ref);
+  tscDebug("%p free sqlObj completed, tscObj:%p ref:%d", ptr, pTscObj, ref);
   if (ref == 0) {
-    tscDebug("%p all sqlObj freed, free tscObj:%p", *p, pTscObj);
+    tscDebug("%p all sqlObj freed, free tscObj:%p", ptr, pTscObj);
     taosRemoveRef(tscRefId, pTscObj->rid);
   }
 }
@@ -644,6 +646,7 @@ int32_t tscCreateDataBlock(size_t initialSize, int32_t rowSize, int32_t startOff
   dataBuf->pData = calloc(1, dataBuf->nAllocSize);
   if (dataBuf->pData == NULL) {
     tscError("failed to allocated memory, reason:%s", strerror(errno));
+    tfree(dataBuf);
     return TSDB_CODE_TSC_OUT_OF_MEMORY;
   }
 
diff --git a/src/common/src/tvariant.c b/src/common/src/tvariant.c
index 6dd0653822..fc00f50a7a 100644
--- a/src/common/src/tvariant.c
+++ b/src/common/src/tvariant.c
@@ -171,7 +171,9 @@ void tVariantAssign(tVariant *pDst, const tVariant *pSrc) {
     }
   }
 
-  pDst->nLen = tDataTypeDesc[pDst->nType].nSize;
+  if (pDst->nType != TSDB_DATA_TYPE_ARRAY) {
+    pDst->nLen = tDataTypeDesc[pDst->nType].nSize;
+  }
 }
 
 int32_t tVariantCompare(const tVariant* p1, const tVariant* p2) {
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 630a469dd7..3fcf44f057 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -6814,7 +6814,7 @@ static int32_t doDumpQueryResult(SQInfo *pQInfo, char *data) {
 
       qDebug("QInfo:%p ts comp data return, file:%s, size:%"PRId64, pQInfo, pQuery->sdata[0]->data, s);
       if (lseek(fd, 0, SEEK_SET) >= 0) {
-        size_t sz = read(fd, data, (uint32_t)s);
+        size_t sz = read(fd, data, (uint32_t) s);
         if(sz < s) {  // todo handle error
           assert(0);
         }
diff --git a/src/query/src/qParserImpl.c b/src/query/src/qParserImpl.c
index 0853565fc6..5cd9d3c77a 100644
--- a/src/query/src/qParserImpl.c
+++ b/src/query/src/qParserImpl.c
@@ -187,7 +187,8 @@ tSQLExpr *tSQLExprCreate(tSQLExpr *pLeft, tSQLExpr *pRight, int32_t optrType) {
     pExpr->token.type = pLeft->token.type;
   }
 
-  if (optrType == TK_PLUS || optrType == TK_MINUS || optrType == TK_STAR || optrType == TK_DIVIDE || optrType == TK_REM) {
+  if ((pLeft != NULL && pRight != NULL) &&
+      (optrType == TK_PLUS || optrType == TK_MINUS || optrType == TK_STAR || optrType == TK_DIVIDE || optrType == TK_REM)) {
     /*
      * if a token is noted as the TK_TIMESTAMP, the time precision is microsecond
      * Otherwise, the time precision is adaptive, determined by the time precision from databases.
diff --git a/src/query/src/qResultbuf.c b/src/query/src/qResultbuf.c
index 67cb7af074..dfa8bcd95b 100644
--- a/src/query/src/qResultbuf.c
+++ b/src/query/src/qResultbuf.c
@@ -119,8 +119,11 @@ static char* doFlushPageToDisk(SDiskbasedResultBuf* pResultBuf, SPageInfo* pg) {
     pg->info.offset = allocatePositionInFile(pResultBuf, size);
     pResultBuf->nextPos += size;
 
-    fseek(pResultBuf->file, pg->info.offset, SEEK_SET);
-    /*int32_t ret =*/ fwrite(t, 1, size, pResultBuf->file);
+    int32_t ret = fseek(pResultBuf->file, pg->info.offset, SEEK_SET);
+    assert(ret == 0);
+
+    ret = fwrite(t, 1, size, pResultBuf->file);
+    assert(ret == size);
 
     if (pResultBuf->fileSize < pg->info.offset + pg->info.length) {
       pResultBuf->fileSize = pg->info.offset + pg->info.length;
diff --git a/src/query/src/qTsbuf.c b/src/query/src/qTsbuf.c
index 8a5a87baab..d0c59fe5ef 100644
--- a/src/query/src/qTsbuf.c
+++ b/src/query/src/qTsbuf.c
@@ -341,8 +341,10 @@ STSBlock* readDataFromDisk(STSBuf* pTSBuf, int32_t order, bool decomp) {
     pBlock->tag.pz = tp;
 
     sz = fread(pBlock->tag.pz, (size_t)pBlock->tag.nLen, 1, pTSBuf->f);
-  } else if (pBlock->tag.nType != TSDB_DATA_TYPE_NULL) {
+    UNUSED(sz);
+  } else if (pBlock->tag.nType != TSDB_DATA_TYPE_NULL) { //TODO check the return value
     sz = fread(&pBlock->tag.i64Key, (size_t) pBlock->tag.nLen, 1, pTSBuf->f);
+    UNUSED(sz);
   }
 
   sz = fread(&pBlock->numOfElem, sizeof(pBlock->numOfElem), 1, pTSBuf->f);
diff --git a/tests/script/general/parser/col_arithmetic_operation.sim b/tests/script/general/parser/col_arithmetic_operation.sim
index c05229ab65..64f41ae11f 100644
--- a/tests/script/general/parser/col_arithmetic_operation.sim
+++ b/tests/script/general/parser/col_arithmetic_operation.sim
@@ -73,7 +73,6 @@ run general/parser/col_arithmetic_query.sim
 print ====================> crash
 # sql select spread(ts )/(1000*3600*24) from ca_stb0 interval(1y)
 
-
 sql_error select first(c1, c2) - last(c1, c2) from stb interval(1y)
 sql_error select first(ts) - last(ts) from stb interval(1y)
 sql_error select top(c1, 2) - last(c1) from stb;

From 2783c56f8ab3b33d7858a67ddab01062adf726cb Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 18:45:09 +0800
Subject: [PATCH 12/41] [TD-225]update script.

---
 .../parser/col_arithmetic_operation.sim       |  68 ++++++--
 .../general/parser/col_arithmetic_query.sim   | 147 ++++++++++++++----
 2 files changed, 175 insertions(+), 40 deletions(-)

diff --git a/tests/script/general/parser/col_arithmetic_operation.sim b/tests/script/general/parser/col_arithmetic_operation.sim
index 64f41ae11f..7adae8ef81 100644
--- a/tests/script/general/parser/col_arithmetic_operation.sim
+++ b/tests/script/general/parser/col_arithmetic_operation.sim
@@ -29,12 +29,41 @@ sql create table $stb (ts timestamp, c1 int, c2 bigint, c3 float, c4 double, c5
 $i = 0
 $ts = $ts0
 $halfTbNum = $tbNum / 2
-while $i < $halfTbNum
-  $tbId = $i + $halfTbNum
-  $tb = $tbPrefix . $i
-  $tb1 = $tbPrefix . $tbId
-  sql create table $tb using $stb tags( $i )
-  sql create table $tb1 using $stb tags( $tbId )
+#while $i < $halfTbNum
+  $t1 = $i + 1
+  $t2 = $i + 2
+  $t3 = $i + 3
+  $t4 = $i + 4
+
+  $t5 = $i + $halfTbNum
+  $t6 = $t5 + 1
+  $t7 = $t6 + 1
+  $t8 = $t7 + 1
+  $t9 = $t8 + 1
+
+  $tb0 = $tbPrefix . $i
+  $tb1 = $tbPrefix . $t1
+  $tb2 = $tbPrefix . $t2
+  $tb3 = $tbPrefix . $t3
+  $tb4 = $tbPrefix . $t4
+
+  $tb5 = $tbPrefix . $t5
+  $tb6 = $tbPrefix . $t6
+  $tb7 = $tbPrefix . $t7
+  $tb8 = $tbPrefix . $t8
+  $tb9 = $tbPrefix . $t9
+
+  sql create table $tb0 using $stb tags( $i )
+  sql create table $tb1 using $stb tags( $t1 )
+  sql create table $tb2 using $stb tags( $t2 )
+  sql create table $tb3 using $stb tags( $t3 )
+  sql create table $tb4 using $stb tags( $t4 )
+
+  sql create table $tb5 using $stb tags( $t5 )
+  sql create table $tb6 using $stb tags( $t6 )
+  sql create table $tb7 using $stb tags( $t7 )
+  sql create table $tb8 using $stb tags( $t8 )
+  sql create table $tb9 using $stb tags( $t9 )
 
   $x = 0
   while $x < $rowNum
@@ -47,11 +76,28 @@ while $i < $halfTbNum
     $binary = $binary . '
     $nchar = 'nchar . $c
     $nchar = $nchar . '
-    sql insert into $tb values ( $ts , $c , $c , $c , $c , $c , $c , true, $binary , $nchar ) $tb1 values ( $ts , NULL , $c , NULL , $c , NULL , $c , NULL, NULL , $nchar )
+    sql insert into $tb0 values ( $ts , $c , $c , $c , $c , $c , $c , true, $binary , $nchar ) $tb1 values ( $ts , $c , $c , $c , $c , $c , $c , true, $binary , $nchar ) $tb2 values ( $ts , $c , $c , $c , $c , $c , $c , true, $binary , $nchar ) $tb3 values ( $ts , $c , $c , $c , $c , $c , $c , true, $binary , $nchar ) $tb4 values ( $ts , $c , $c , $c , $c , $c , $c , true, $binary , $nchar )
     $x = $x + 1
-  endw 
-  $i = $i + 1
-endw 
+  endw
+  #$i = $i + 1
+
+  $x = 0
+  while $x < $rowNum
+    $xs = $x * $delta
+    $ts = $ts0 + $xs
+    $c = $x / 10
+    $c = $c * 10
+    $c = $x - $c
+    $binary = 'binary . $c
+    $binary = $binary . '
+    $nchar = 'nchar . $c
+    $nchar = $nchar . '
+
+    sql insert into $tb5 values ( $ts , NULL , $c , NULL , $c , NULL , $c , NULL, NULL , $nchar ) $tb6 values ( $ts , NULL , $c , NULL , $c , NULL , $c , NULL, NULL , $nchar ) $tb7 values ( $ts , NULL , $c , NULL , $c , NULL , $c , NULL, NULL , $nchar ) $tb8 values ( $ts , NULL , $c , NULL , $c , NULL , $c , NULL, NULL , $nchar ) $tb9 values ( $ts , NULL , $c , NULL , $c , NULL , $c , NULL, NULL , $nchar )
+    $x = $x + 1
+  endw
+
+#endw
 
 #=================================== above are setup test environment =============================
 run general/parser/col_arithmetic_query.sim
@@ -64,7 +110,7 @@ system sh/exec.sh -n dnode1 -s start
 
 print ================== server restart completed
 sql connect
-sleep 500
+sleep 500c
 
 run general/parser/col_arithmetic_query.sim
 
diff --git a/tests/script/general/parser/col_arithmetic_query.sim b/tests/script/general/parser/col_arithmetic_query.sim
index 95258168ef..61a48e4a80 100644
--- a/tests/script/general/parser/col_arithmetic_query.sim
+++ b/tests/script/general/parser/col_arithmetic_query.sim
@@ -1,6 +1,17 @@
 # ======================================= query test cases ========================================
 # select from table
 
+$dbPrefix = ca_db
+$tbPrefix = ca_tb
+$stbPrefix = ca_stb
+$rowNum = 10000
+
+$i = 0
+$db = $dbPrefix . $i
+
+$db = $dbPrefix . $i
+sql use $db
+
 $tb = $tbPrefix . 0
 ## TBASE-344
 sql select c1*2 from $tb
@@ -20,38 +31,100 @@ if $data90 != 18.000000000 then
   return -1
 endi
 
-# asc/desc order [d.2]
+# asc/desc order [d.2] ======================================================
 sql select c1 *( 2 / 3 ), c1/c1 from $tb order by ts asc;
+if $rows != 10000 then
+  return -1
+endi
+
+if $data00 != 0.000000000 then
+  return -1
+endi
+
+if $data01 != NaN then
+  return -1
+endi
+
+if $data10 != 0.666666667 then
+  return -1
+endi
+
+if $data11 != 1.000000000 then
+  return -1
+endi
+
+if $data90 != 6.000000000 then
+  return -1
+endi
+
+if $data91 != 1.000000000 then
+  return -1
+endi
+
 sql select (c1 * 2) % 7.9 from $tb order by ts desc;
+if $rows != 10000 then
+ return -1
+endi
 
-sql select c1 * c2 /4 from $tb where ts <  and ts >
+if $data00 != 0.100000000 then
+  return -1
+endi
 
-# no result return [d.3]
-sql select c1 * 91- 7 from $tb where ts<1537146000000
+if $data10 != 2.100000000 then
+  return -1
+endi
+
+if $data90 != 6.000000000 then
+ return -1
+endi
+
+# [d.3]
+sql select c1 * c2 /4 from $tb where ts < 1537166000000 and ts > 1537156000000
+if $rows != 17 then
+  return -1
+endi
+
+if $data00 != 12.250000000 then
+  return -1
+endi
+
+if $data10 != 16.000000000 then
+  return -1
+endi
+
+if $data21 != 20.250000000 then
+  return -1
+endi
+
+if $data31 != 0.000000000 then
+  return -1
+endi
+
+
+# no result return [d.3] ==============================================================
+sql select c1 * 91- 7 from $tb where ts < 1537146000000
 if $rows != 0 then
   return -1
 endi
 
 # no result return [d.3]
-sql select c2 - c2 from $tb where ts>xxx
+sql select c2 - c2 from $tb where ts > '2018-09-17 12:50:00.000' and ts<'2018-09-17 13:00:00.000'
 if $rows != 0 then
   return -1
 endi
 
-# single row result aggregation [d.4]
+# single row result aggregation [d.4] =================================================
 # not available
 
 # error cases
-sql_error select first(c1,c2) - last(c1,c2) from $tb
+# not available
 
 # multi row result aggregation [d.4]
 sql select top(c1, 1) - bottom(c1, 1) from $tb
 sql select top(c1, 99) - bottom(c1, 99) from $tb
 
-# all data types [d.6]
-sql select c2-c1, c3/c2, c4*c3, c5%c4, c6+99%22 from $tb
-
-
+# all data types [d.6] ================================================================
+sql select c2-c1, c3/c2, c4*c3, c5%c4, c6+99%22, c2-c2 from $tb
 
 # error case, ts/bool/binary/nchar not support arithmetic expression
 sql_error select ts+ts from $tb
@@ -65,41 +138,57 @@ sql_error select c8+c7, c9+c9+c8+c7/c6 from $tb
 sql_error select c1/0, c2/0, c3/0.0 from $tb
 sql_error select c1/0.00000000001 from $tb
 
-# arithmetic expression in join [d.7]
+# arithmetic expression in join [d.7]==================================================
 
 
-# arithmetic expression in union [d.8]
+# arithmetic expression in union [d.8]=================================================
 
 
-# arithmetic expression in group by [d.9]
-# in group by tag
-# not support for normal table
+# arithmetic expression in group by [d.9]==============================================
+# in group by tag, not support for normal table
 sql_error select c5*99 from $tb group by t1
 
 # in group by column
 sql_error select c6-(c6+c3)*12 from $tb group by c3;
 
 
-# limit offset [d.10]
-sql select c6 - c6 + 12 from $tb limit 12 offset 99;
-sql select c4 / 99.123 from $tb limit 1 offset 9999;
+# limit offset [d.10]==================================================================
+sql select c6 * c1 + 12 from $tb limit 12 offset 99;
+if $rows != 12 then
+ return -1
+endi
 
-# slimit/soffset not support for normal table query. [d.11]
+if $data00 != 93.000000000 then
+  return -1
+endi
+
+if $data90 != 12.000000000 then
+  return -1
+endi
+
+sql select c4 / 99.123 from $tb limit 10 offset 9999;
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 !=
+
+# slimit/soffset not support for normal table query. [d.11]============================
 sql_error select sum(c1) from $tb slimit 1 soffset 19;
 
-# fill [d.12]
+# fill [d.12]==========================================================================
 sql_error select c2-c2, c3-c4, c5%c6 from $tb fill(value, 12);
 
-# constant column. [d.13]
+# constant column. [d.13]==============================================================
 
 
-# column value filter [d.14]
+# column value filter [d.14]===========================================================
 
 
-# tag filter(not support for normal table). [d.15]
+# tag filter(not support for normal table). [d.15]=====================================
 sql_error select c2+99 from $tb where t1=12;
 
-# multi-field output [d.16]
+# multi-field output [d.16]============================================================
 sql select count(*), sum(c1)*avg(c2), avg(c3)*count(c3), sum(c3), sum(c4), first(c7), last(c8), first(c9), first(c7), last(c8) from $tb
 
 sql select c4*1+1/2 from $tb
@@ -116,17 +205,17 @@ if $data90 != 9.500000000 then
   return -1
 endi
 
-# interval query [d.17]
+# interval query [d.17]==================================================================
 sql_error select c2*c2, c3-c3, c4+9 from $tb interval(1s)
 sql_error select c7-c9 from $tb interval(2y)
 
-# aggregation query [d.18]
+# aggregation query [d.18]===============================================================
 # see test cases below
 
-# first/last query  [d.19]
+# first/last query  [d.19]===============================================================
 # see test cases below
 
-# multiple retrieve [d.20]
+# multiple retrieve [d.20]===============================================================
 sql select c2-c2 from $tb;
 
 #======================================= aggregation function arithmetic query cases ================

From dd9228e06733c5a775e953e01b1bd12e1711a5e4 Mon Sep 17 00:00:00 2001
From: zyyang <zyyang@taosdata.com>
Date: Mon, 23 Nov 2020 18:51:13 +0800
Subject: [PATCH 13/41] [TD-1859]<feature>: restful implementation for
 taos-jdbc

---
 src/connector/jdbc/deploy-pom.xml             |   2 +-
 src/connector/jdbc/pom.xml                    |   9 +-
 .../taosdata/jdbc/rs/RestfulConnection.java   |  41 ++++---
 .../com/taosdata/jdbc/rs/RestfulDriver.java   |   2 +-
 .../taosdata/jdbc/rs/RestfulStatement.java    |  71 ++++++++++--
 .../jdbc/utils/SqlSyntaxValidator.java        |  29 ++++-
 .../taosdata/jdbc/rs/RestfulDriverTest.java   |  23 ----
 .../com/taosdata/jdbc/rs/RestfulJDBCTest.java | 108 ++++++++++++++++++
 .../jdbc/utils/SqlSyntaxValidatorTest.java    |  29 +++++
 9 files changed, 263 insertions(+), 51 deletions(-)
 create mode 100644 src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulJDBCTest.java
 create mode 100644 src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java

diff --git a/src/connector/jdbc/deploy-pom.xml b/src/connector/jdbc/deploy-pom.xml
index 51db837c7b..46de54ffb2 100755
--- a/src/connector/jdbc/deploy-pom.xml
+++ b/src/connector/jdbc/deploy-pom.xml
@@ -5,7 +5,7 @@
 
   <groupId>com.taosdata.jdbc</groupId>
   <artifactId>taos-jdbcdriver</artifactId>
-  <version>2.0.10</version>
+  <version>2.0.13</version>
   <packaging>jar</packaging>
 
   <name>JDBCDriver</name>
diff --git a/src/connector/jdbc/pom.xml b/src/connector/jdbc/pom.xml
index e7124a0599..3d1f402435 100755
--- a/src/connector/jdbc/pom.xml
+++ b/src/connector/jdbc/pom.xml
@@ -3,7 +3,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.taosdata.jdbc</groupId>
     <artifactId>taos-jdbcdriver</artifactId>
-    <version>2.0.8</version>
+    <version>2.0.13</version>
     <packaging>jar</packaging>
     <name>JDBCDriver</name>
     <url>https://github.com/taosdata/TDengine/tree/master/src/connector/jdbc</url>
@@ -112,6 +112,13 @@
                 <artifactId>maven-surefire-plugin</artifactId>
                 <version>2.12.4</version>
                 <configuration>
+                    <includes>
+                        <include>**/*Test.java</include>
+                    </includes>
+                    <excludes>
+                        <exclude>**/BatchInsertTest.java</exclude>
+                        <exclude>**/FailOverTest.java</exclude>
+                    </excludes>
                     <testFailureIgnore>true</testFailureIgnore>
                 </configuration>
             </plugin>
diff --git a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulConnection.java b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulConnection.java
index b82efca3ef..6b0937a9b7 100644
--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulConnection.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulConnection.java
@@ -15,7 +15,6 @@ public class RestfulConnection implements Connection {
     private final String database;
     private final String url;
 
-
     public RestfulConnection(String host, String port, Properties props, String database, String url) {
         this.host = host;
         this.port = Integer.parseInt(port);
@@ -28,7 +27,7 @@ public class RestfulConnection implements Connection {
     public Statement createStatement() throws SQLException {
         if (isClosed())
             throw new SQLException(TSDBConstants.WrapErrMsg("restful TDengine connection is closed."));
-        return new RestfulStatement(this, this.database);
+        return new RestfulStatement(this, database);
     }
 
     @Override
@@ -104,22 +103,28 @@ public class RestfulConnection implements Connection {
 
     @Override
     public void setTransactionIsolation(int level) throws SQLException {
-
+        //transaction is not supported
+        throw new SQLFeatureNotSupportedException("transactions are not supported");
     }
 
+    /**
+     *
+     */
     @Override
     public int getTransactionIsolation() throws SQLException {
-        return 0;
+        //Connection.TRANSACTION_NONE specifies that transactions are not supported.
+        return Connection.TRANSACTION_NONE;
     }
 
     @Override
     public SQLWarning getWarnings() throws SQLException {
+        //TODO: getWarnings not implemented
         return null;
     }
 
     @Override
     public void clearWarnings() throws SQLException {
-
+        throw new SQLFeatureNotSupportedException("clearWarnings not supported.");
     }
 
     @Override
@@ -209,22 +214,26 @@ public class RestfulConnection implements Connection {
 
     @Override
     public Clob createClob() throws SQLException {
-        return null;
+        //TODO: not supported
+        throw new SQLFeatureNotSupportedException();
     }
 
     @Override
     public Blob createBlob() throws SQLException {
-        return null;
+        //TODO: not supported
+        throw new SQLFeatureNotSupportedException();
     }
 
     @Override
     public NClob createNClob() throws SQLException {
-        return null;
+        //TODO: not supported
+        throw new SQLFeatureNotSupportedException();
     }
 
     @Override
     public SQLXML createSQLXML() throws SQLException {
-        return null;
+        //TODO: not supported
+        throw new SQLFeatureNotSupportedException();
     }
 
     @Override
@@ -254,12 +263,14 @@ public class RestfulConnection implements Connection {
 
     @Override
     public Array createArrayOf(String typeName, Object[] elements) throws SQLException {
-        return null;
+        //TODO: not supported
+        throw new SQLFeatureNotSupportedException();
     }
 
     @Override
     public Struct createStruct(String typeName, Object[] attributes) throws SQLException {
-        return null;
+        //TODO: not supported
+        throw new SQLFeatureNotSupportedException();
     }
 
     @Override
@@ -289,12 +300,16 @@ public class RestfulConnection implements Connection {
 
     @Override
     public <T> T unwrap(Class<T> iface) throws SQLException {
-        return null;
+        try {
+            return iface.cast(this);
+        } catch (ClassCastException cce) {
+            throw new SQLException("Unable to unwrap to " + iface.toString());
+        }
     }
 
     @Override
     public boolean isWrapperFor(Class<?> iface) throws SQLException {
-        return false;
+        return iface.isInstance(this);
     }
 
     public String getHost() {
diff --git a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulDriver.java b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulDriver.java
index a07d6eb2b6..9e87cfa680 100644
--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulDriver.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulDriver.java
@@ -35,7 +35,7 @@ public class RestfulDriver extends AbstractTaosDriver {
         Properties props = parseURL(url, info);
         String host = props.getProperty(TSDBDriver.PROPERTY_KEY_HOST, "localhost");
         String port = props.getProperty(TSDBDriver.PROPERTY_KEY_PORT, "6041");
-        String database = props.getProperty(TSDBDriver.PROPERTY_KEY_DBNAME);
+        String database = props.containsKey(TSDBDriver.PROPERTY_KEY_DBNAME) ? props.getProperty(TSDBDriver.PROPERTY_KEY_DBNAME) : null;
 
         String loginUrl = "http://" + props.getProperty(TSDBDriver.PROPERTY_KEY_HOST) + ":"
                 + props.getProperty(TSDBDriver.PROPERTY_KEY_PORT) + "/rest/login/"
diff --git a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulStatement.java b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulStatement.java
index 20510f0135..30b56638d8 100644
--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulStatement.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulStatement.java
@@ -4,6 +4,7 @@ import com.alibaba.fastjson.JSON;
 import com.alibaba.fastjson.JSONObject;
 import com.taosdata.jdbc.TSDBConstants;
 import com.taosdata.jdbc.rs.util.HttpClientPoolUtil;
+import com.taosdata.jdbc.utils.SqlSyntaxValidator;
 
 import java.sql.*;
 import java.util.Arrays;
@@ -11,19 +12,23 @@ import java.util.List;
 
 public class RestfulStatement implements Statement {
 
-    private final String catalog;
+    private boolean closed;
+    private String database;
     private final RestfulConnection conn;
 
-    public RestfulStatement(RestfulConnection c, String catalog) {
+    public RestfulStatement(RestfulConnection c, String database) {
         this.conn = c;
-        this.catalog = catalog;
+        this.database = database;
     }
 
     @Override
     public ResultSet executeQuery(String sql) throws SQLException {
+        if (isClosed())
+            throw new SQLException("statement already closed");
+        if (!SqlSyntaxValidator.isSelectSql(sql))
+            throw new SQLException("not a select sql for executeQuery: " + sql);
 
-        final String url = "http://" + conn.getHost() + ":"+conn.getPort()+"/rest/sql";
-
+        final String url = "http://" + conn.getHost() + ":" + conn.getPort() + "/rest/sql";
         String result = HttpClientPoolUtil.execute(url, sql);
         String fields = "";
         List<String> words = Arrays.asList(sql.split(" "));
@@ -65,12 +70,29 @@ public class RestfulStatement implements Statement {
 
     @Override
     public int executeUpdate(String sql) throws SQLException {
-        return 0;
+        if (isClosed())
+            throw new SQLException("statement already closed");
+        if (!SqlSyntaxValidator.isValidForExecuteUpdate(sql))
+            throw new SQLException("not a valid sql for executeUpdate: " + sql);
+
+        if (this.database == null)
+            throw new SQLException("Database not specified or available");
+
+        final String url = "http://" + conn.getHost() + ":" + conn.getPort() + "/rest/sql";
+        HttpClientPoolUtil.execute(url, "use " + conn.getDatabase());
+        String result = HttpClientPoolUtil.execute(url, sql);
+        JSONObject jsonObject = JSON.parseObject(result);
+        if (jsonObject.getString("status").equals("error")) {
+            throw new SQLException(TSDBConstants.WrapErrMsg("SQL execution error: " +
+                    jsonObject.getString("desc") + "\n" +
+                    "error code: " + jsonObject.getString("code")));
+        }
+        return Integer.parseInt(jsonObject.getString("rows"));
     }
 
     @Override
     public void close() throws SQLException {
-
+        this.closed = true;
     }
 
     @Override
@@ -115,6 +137,7 @@ public class RestfulStatement implements Statement {
 
     @Override
     public SQLWarning getWarnings() throws SQLException {
+        //TODO: getWarnings not Implemented
         return null;
     }
 
@@ -130,7 +153,29 @@ public class RestfulStatement implements Statement {
 
     @Override
     public boolean execute(String sql) throws SQLException {
-        return false;
+        if (isClosed()) {
+            throw new SQLException("Invalid method call on a closed statement.");
+        }
+        //如果执行了use操作应该将当前Statement的catalog设置为新的database
+        if (SqlSyntaxValidator.isUseSql(sql)) {
+            this.database = sql.trim().replace("use", "").trim();
+        }
+        if (this.database == null)
+            throw new SQLException("Database not specified or available");
+
+        final String url = "http://" + conn.getHost() + ":" + conn.getPort() + "/rest/sql";
+        // use database
+        HttpClientPoolUtil.execute(url, "use " + conn.getDatabase());
+        // execute sql
+        String result = HttpClientPoolUtil.execute(url, sql);
+        // parse result
+        JSONObject jsonObject = JSON.parseObject(result);
+        if (jsonObject.getString("status").equals("error")) {
+            throw new SQLException(TSDBConstants.WrapErrMsg("SQL execution error: " +
+                    jsonObject.getString("desc") + "\n" +
+                    "error code: " + jsonObject.getString("code")));
+        }
+        return true;
     }
 
     @Override
@@ -245,7 +290,7 @@ public class RestfulStatement implements Statement {
 
     @Override
     public boolean isClosed() throws SQLException {
-        return false;
+        return closed;
     }
 
     @Override
@@ -270,11 +315,15 @@ public class RestfulStatement implements Statement {
 
     @Override
     public <T> T unwrap(Class<T> iface) throws SQLException {
-        return null;
+        try {
+            return iface.cast(this);
+        } catch (ClassCastException cce) {
+            throw new SQLException("Unable to unwrap to " + iface.toString());
+        }
     }
 
     @Override
     public boolean isWrapperFor(Class<?> iface) throws SQLException {
-        return false;
+        return iface.isInstance(this);
     }
 }
diff --git a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/SqlSyntaxValidator.java b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/SqlSyntaxValidator.java
index 066dfad5d5..388c3978be 100644
--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/SqlSyntaxValidator.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/SqlSyntaxValidator.java
@@ -22,6 +22,9 @@ import java.sql.SQLException;
 
 public class SqlSyntaxValidator {
 
+    private static final String[] updateSQL = {"insert", "update", "delete", "create", "alter", "drop", "show", "describe", "use"};
+    private static final String[] querySQL = {"select"};
+
     private TSDBConnection tsdbConnection;
 
     public SqlSyntaxValidator(Connection connection) {
@@ -34,7 +37,7 @@ public class SqlSyntaxValidator {
         if (tsdbConnection == null || tsdbConnection.isClosed()) {
             throw new SQLException("invalid connection");
         } else {
-            TSDBJNIConnector jniConnector  = tsdbConnection.getConnection();
+            TSDBJNIConnector jniConnector = tsdbConnection.getConnection();
             if (jniConnector == null) {
                 throw new SQLException("jniConnector is null");
             } else {
@@ -43,4 +46,28 @@ public class SqlSyntaxValidator {
         }
         return res;
     }
+
+    public static boolean isValidForExecuteUpdate(String sql) {
+        for (String prefix : updateSQL) {
+            if (sql.trim().toLowerCase().startsWith(prefix))
+                return true;
+        }
+        return false;
+    }
+
+    public static boolean isUseSql(String sql) {
+        return sql.trim().toLowerCase().startsWith(updateSQL[8]) || sql.trim().toLowerCase().matches("create\\s*database.*") || sql.toLowerCase().toLowerCase().matches("drop\\s*database.*");
+    }
+
+    public static boolean isUpdateSql(String sql) {
+        return sql.trim().toLowerCase().startsWith(updateSQL[1]);
+    }
+
+    public static boolean isInsertSql(String sql) {
+        return sql.trim().toLowerCase().startsWith(updateSQL[0]);
+    }
+
+    public static boolean isSelectSql(String sql) {
+        return sql.trim().toLowerCase().startsWith(querySQL[0]);
+    }
 }
diff --git a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDriverTest.java b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDriverTest.java
index 768eceab8e..d07a6a2179 100644
--- a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDriverTest.java
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDriverTest.java
@@ -7,29 +7,6 @@ import java.sql.*;
 
 public class RestfulDriverTest {
 
-    @Test
-    public void testCase001() {
-        try {
-            Class.forName("com.taosdata.jdbc.rs.RestfulDriver");
-            Connection connection = DriverManager.getConnection("jdbc:TAOS-RS://master:6041/?user=root&password=taosdata");
-            Statement statement = connection.createStatement();
-            ResultSet resultSet = statement.executeQuery("select * from log.log");
-            ResultSetMetaData metaData = resultSet.getMetaData();
-            while (resultSet.next()) {
-                for (int i = 1; i <= metaData.getColumnCount(); i++) {
-                    String column = metaData.getColumnLabel(i);
-                    String value = resultSet.getString(i);
-                    System.out.print(column + ":" + value + "\t");
-                }
-                System.out.println();
-            }
-            statement.close();
-            connection.close();
-        } catch (SQLException | ClassNotFoundException e) {
-            e.printStackTrace();
-        }
-    }
-
     @Test
     public void connect() {
 
diff --git a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulJDBCTest.java b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulJDBCTest.java
new file mode 100644
index 0000000000..d13475b96d
--- /dev/null
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulJDBCTest.java
@@ -0,0 +1,108 @@
+package com.taosdata.jdbc.rs;
+
+import org.junit.*;
+import org.junit.runners.MethodSorters;
+
+import java.sql.*;
+import java.util.Random;
+
+@FixMethodOrder(MethodSorters.NAME_ASCENDING)
+public class RestfulJDBCTest {
+
+    private Connection connection;
+
+    @Before
+    public void before() throws ClassNotFoundException, SQLException {
+        Class.forName("com.taosdata.jdbc.rs.RestfulDriver");
+        connection = DriverManager.getConnection("jdbc:TAOS-RS://master:6041/restful_test?user=root&password=taosdata");
+    }
+
+    @After
+    public void after() throws SQLException {
+        if (connection != null)
+            connection.close();
+    }
+
+
+    /**
+     * 查询所有log.log
+     **/
+    @Test
+    public void testCase001() {
+        try {
+            Statement statement = connection.createStatement();
+            ResultSet resultSet = statement.executeQuery("select * from log.log");
+            ResultSetMetaData metaData = resultSet.getMetaData();
+            while (resultSet.next()) {
+                for (int i = 1; i <= metaData.getColumnCount(); i++) {
+                    String column = metaData.getColumnLabel(i);
+                    String value = resultSet.getString(i);
+                    System.out.print(column + ":" + value + "\t");
+                }
+                System.out.println();
+            }
+            statement.close();
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+    }
+
+    /**
+     * create database
+     */
+    @Test
+    public void testCase002() {
+        try (Statement stmt = connection.createStatement()) {
+            stmt.execute("drop database if exists restful_test");
+            stmt.execute("create database if not exists restful_test");
+            stmt.execute("use restful_test");
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+    }
+
+    /**
+     * create super table
+     ***/
+    @Test
+    public void testCase003() {
+        try (Statement stmt = connection.createStatement()) {
+            stmt.execute("create table weather(ts timestamp, temperature float, humidity int) tags(location nchar(64), groupId int)");
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+    }
+
+    @Test
+    public void testCase004() {
+        try (Statement stmt = connection.createStatement()) {
+            for (int i = 1; i <= 100; i++) {
+                stmt.execute("create table t" + i + " using weather tags('beijing', '" + i + "')");
+            }
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+    }
+
+    private Random random = new Random(System.currentTimeMillis());
+
+    @Test
+    public void testCase005() {
+        try (Statement stmt = connection.createStatement()) {
+            int rows = 0;
+            for (int i = 0; i < 10; i++) {
+                for (int j = 1; j <= 100; j++) {
+                    long currentTimeMillis = System.currentTimeMillis();
+                    int affectRows = stmt.executeUpdate("insert into t" + j + " values(" + currentTimeMillis + "," + (random.nextFloat() * 50) + "," + random.nextInt(100) + ")");
+                    Assert.assertEquals(1, affectRows);
+                    rows += affectRows;
+                }
+            }
+            Assert.assertEquals(1000, rows);
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+    }
+
+
+}
diff --git a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java
new file mode 100644
index 0000000000..25c6c4913d
--- /dev/null
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java
@@ -0,0 +1,29 @@
+package com.taosdata.jdbc.utils;
+
+import com.sun.source.tree.AssertTree;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class SqlSyntaxValidatorTest {
+
+    @Test
+    public void validateSqlSyntax() {
+    }
+
+    @Test
+    public void isSelectSQL() {
+        Assert.assertTrue(SqlSyntaxValidator.isSelectSql("select * from test.weather"));
+        Assert.assertTrue(SqlSyntaxValidator.isSelectSql(" select * from test.weather"));
+        Assert.assertTrue(SqlSyntaxValidator.isSelectSql(" select * from test.weather "));
+        Assert.assertFalse(SqlSyntaxValidator.isSelectSql("insert into test.weather values(now, 1.1, 2)"));
+    }
+
+    @Test
+    public void isUseSQL() {
+        Assert.assertTrue(SqlSyntaxValidator.isUseSql("use database test"));
+        Assert.assertTrue(SqlSyntaxValidator.isUseSql("create database test"));
+        Assert.assertTrue(SqlSyntaxValidator.isUseSql("create database if not exist test"));
+        Assert.assertTrue(SqlSyntaxValidator.isUseSql("drop database test"));
+        Assert.assertTrue(SqlSyntaxValidator.isUseSql("drop database if exist test"));
+    }
+}
\ No newline at end of file

From f26fc83be8c8523e140adef265d74529447e27d9 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 23 Nov 2020 18:59:13 +0800
Subject: [PATCH 14/41] [TD-2193]<fix>: fix the offset error in arithmetic
 expression.

---
 src/query/src/qExecutor.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 3fcf44f057..2623c74e45 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -947,7 +947,7 @@ static char *getDataBlock(SQueryRuntimeEnv *pRuntimeEnv, SArithmeticSupport *sas
   if (functionId == TSDB_FUNC_ARITHM) {
     sas->pArithExpr = &pQuery->pExpr1[col];
 
-    sas->offset  = 0;
+    sas->offset  = pQuery->pos;
     sas->colList = pQuery->colList;
     sas->numOfCols = pQuery->numOfCols;
     sas->data    = calloc(pQuery->numOfCols, POINTER_BYTES);

From a9e43baa3f8841d468efe1fedb5beda78beeb49d Mon Sep 17 00:00:00 2001
From: zyyang <zyyang@taosdata.com>
Date: Mon, 23 Nov 2020 19:08:03 +0800
Subject: [PATCH 15/41] change

---
 .../java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java     | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java
index 25c6c4913d..fb570e16c4 100644
--- a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/SqlSyntaxValidatorTest.java
@@ -1,6 +1,5 @@
 package com.taosdata.jdbc.utils;
 
-import com.sun.source.tree.AssertTree;
 import org.junit.Assert;
 import org.junit.Test;
 

From 0481d9836f33f6e0a1e26e85af7a4bdc5a8ea49d Mon Sep 17 00:00:00 2001
From: zyyang <zyyang@taosdata.com>
Date: Mon, 23 Nov 2020 19:12:07 +0800
Subject: [PATCH 16/41] change

---
 src/connector/jdbc/CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/connector/jdbc/CMakeLists.txt b/src/connector/jdbc/CMakeLists.txt
index c565853ab0..701a39b209 100644
--- a/src/connector/jdbc/CMakeLists.txt
+++ b/src/connector/jdbc/CMakeLists.txt
@@ -8,7 +8,7 @@ IF (TD_MVN_INSTALLED)
   ADD_CUSTOM_COMMAND(OUTPUT ${JDBC_CMD_NAME}
     POST_BUILD
     COMMAND mvn -Dmaven.test.skip=true install -f ${CMAKE_CURRENT_SOURCE_DIR}/pom.xml
-    COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_SOURCE_DIR}/target/taos-jdbcdriver-2.0.8-dist.jar ${LIBRARY_OUTPUT_PATH}
+    COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_SOURCE_DIR}/target/taos-jdbcdriver-2.0.13-dist.jar ${LIBRARY_OUTPUT_PATH}
     COMMAND mvn -Dmaven.test.skip=true clean -f ${CMAKE_CURRENT_SOURCE_DIR}/pom.xml
     COMMENT "build jdbc driver")
   ADD_CUSTOM_TARGET(${JDBC_TARGET_NAME} ALL WORKING_DIRECTORY ${EXECUTABLE_OUTPUT_PATH} DEPENDS ${JDBC_CMD_NAME})

From 5e91e8e307c232e9eaf47615499c6a7d0dc5a936 Mon Sep 17 00:00:00 2001
From: zyyang <zyyang@taosdata.com>
Date: Mon, 23 Nov 2020 19:28:45 +0800
Subject: [PATCH 17/41] change

---
 cmake/install.inc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cmake/install.inc b/cmake/install.inc
index 9bbcc2cf40..4886e79e73 100755
--- a/cmake/install.inc
+++ b/cmake/install.inc
@@ -32,7 +32,7 @@ ELSEIF (TD_WINDOWS)
   #INSTALL(TARGETS taos RUNTIME DESTINATION driver)
   #INSTALL(TARGETS shell RUNTIME DESTINATION .)
   IF (TD_MVN_INSTALLED)
-    INSTALL(FILES ${LIBRARY_OUTPUT_PATH}/taos-jdbcdriver-2.0.8-dist.jar DESTINATION connector/jdbc)
+    INSTALL(FILES ${LIBRARY_OUTPUT_PATH}/taos-jdbcdriver-2.0.13-dist.jar DESTINATION connector/jdbc)
   ENDIF ()
 ELSEIF (TD_DARWIN)
   SET(TD_MAKE_INSTALL_SH "${TD_COMMUNITY_DIR}/packaging/tools/make_install.sh")

From 7c9ce886942275ffbee67d15b80eff42954fe109 Mon Sep 17 00:00:00 2001
From: zyyang <zyyang@taosdata.com>
Date: Tue, 24 Nov 2020 09:18:55 +0800
Subject: [PATCH 18/41] change

---
 src/connector/jdbc/deploy-pom.xml | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/src/connector/jdbc/deploy-pom.xml b/src/connector/jdbc/deploy-pom.xml
index 46de54ffb2..1dc2625e62 100755
--- a/src/connector/jdbc/deploy-pom.xml
+++ b/src/connector/jdbc/deploy-pom.xml
@@ -49,17 +49,29 @@
         </exclusion>
       </exclusions>
     </dependency>
-    <dependency>
-      <groupId>org.apache.commons</groupId>
-      <artifactId>commons-lang3</artifactId>
-      <version>3.5</version>
-    </dependency>
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
       <version>4.13</version>
       <scope>test</scope>
     </dependency>
+
+    <!-- for restful -->
+    <dependency>
+      <groupId>org.apache.httpcomponents</groupId>
+      <artifactId>httpclient</artifactId>
+      <version>4.5.8</version>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.commons</groupId>
+      <artifactId>commons-lang3</artifactId>
+      <version>3.9</version>
+    </dependency>
+    <dependency>
+      <groupId>com.alibaba</groupId>
+      <artifactId>fastjson</artifactId>
+      <version>1.2.58</version>
+    </dependency>
   </dependencies>
 
   <build>

From e3fc92c9f42c078e4f0cd360ab9e3def1d536ad6 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Tue, 24 Nov 2020 10:24:43 +0800
Subject: [PATCH 19/41] [TD-225] fix bugs.

---
 src/client/src/tscSQLParser.c | 18 +++++++++++++-----
 src/query/src/qExecutor.c     |  6 +++---
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index f859d2969e..743cb42eb3 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -1767,10 +1767,10 @@ static int32_t setExprInfoForFunctions(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SS
   return TSDB_CODE_SUCCESS;
 }
 
-void setResultColName(char* name, tSQLExprItem* pItem, int32_t functionId, SStrToken* pToken) {
+void setResultColName(char* name, tSQLExprItem* pItem, int32_t functionId, SStrToken* pToken, bool multiCols) {
   if (pItem->aliasName != NULL) {
     tstrncpy(name, pItem->aliasName, TSDB_COL_NAME_LEN);
-  } else {
+  } else if (multiCols) {
     char uname[TSDB_COL_NAME_LEN] = {0};
     int32_t len = MIN(pToken->n + 1, TSDB_COL_NAME_LEN);
     tstrncpy(uname, pToken->z, len);
@@ -1781,6 +1781,9 @@ void setResultColName(char* name, tSQLExprItem* pItem, int32_t functionId, SStrT
     snprintf(tmp, size, "%s(%s)", aAggs[functionId].aName, uname);
 
     tstrncpy(name, tmp, TSDB_COL_NAME_LEN);
+  } else  { // use the user-input result column name
+    int32_t len = MIN(pItem->pNode->token.n + 1, TSDB_COL_NAME_LEN);
+    tstrncpy(name, pItem->pNode->token.z, len);
   }
 }
 
@@ -2055,7 +2058,7 @@ int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int32_t col
             for (int32_t j = 0; j < tscGetNumOfColumns(pTableMetaInfo->pTableMeta); ++j) {
               index.columnIndex = j;
               SStrToken t = {.z = pSchema[j].name, .n = (uint32_t)strnlen(pSchema[j].name, TSDB_COL_NAME_LEN)};
-              setResultColName(name, pItem, cvtFunc.originFuncId, &t);
+              setResultColName(name, pItem, cvtFunc.originFuncId, &t, true);
 
               if (setExprInfoForFunctions(pCmd, pQueryInfo, &pSchema[j], cvtFunc, name, colIndex++, &index, finalResult) != 0) {
                 return TSDB_CODE_TSC_INVALID_SQL;
@@ -2077,7 +2080,9 @@ int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int32_t col
             char name[TSDB_COL_NAME_LEN] = {0};
 
             SSchema* pSchema = tscGetTableColumnSchema(pTableMetaInfo->pTableMeta, index.columnIndex);
-            setResultColName(name, pItem, cvtFunc.originFuncId, &pParamElem->pNode->colInfo);
+
+            bool multiColOutput = pItem->pNode->pParam->nExpr > 1;
+            setResultColName(name, pItem, cvtFunc.originFuncId, &pParamElem->pNode->colInfo, multiColOutput);
 
             if (setExprInfoForFunctions(pCmd, pQueryInfo, pSchema, cvtFunc, name, colIndex + i, &index, finalResult) != 0) {
               return TSDB_CODE_TSC_INVALID_SQL;
@@ -2119,7 +2124,7 @@ int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int32_t col
 
             char name[TSDB_COL_NAME_LEN] = {0};
             SStrToken t = {.z = pSchema[i].name, .n = (uint32_t)strnlen(pSchema[i].name, TSDB_COL_NAME_LEN)};
-            setResultColName(name, pItem, cvtFunc.originFuncId, &t);
+            setResultColName(name, pItem, cvtFunc.originFuncId, &t, true);
 
             if (setExprInfoForFunctions(pCmd, pQueryInfo, &pSchema[index.columnIndex], cvtFunc, name, colIndex, &index, finalResult) != 0) {
               return TSDB_CODE_TSC_INVALID_SQL;
@@ -4243,6 +4248,9 @@ static int32_t getTagQueryCondExpr(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SCondE
     tExprTreeDestroy(&p, NULL);
     
     taosArrayDestroy(colList);
+    if (taosArrayGetSize(pQueryInfo->tagCond.pCond) > 0 && !UTIL_TABLE_IS_SUPER_TABLE(pTableMetaInfo)) {
+      return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), "filter on tag not supported for normal table");
+    }
   }
 
   pCondExpr->pTagCond = NULL;
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 2623c74e45..7d6068ff64 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -947,10 +947,10 @@ static char *getDataBlock(SQueryRuntimeEnv *pRuntimeEnv, SArithmeticSupport *sas
   if (functionId == TSDB_FUNC_ARITHM) {
     sas->pArithExpr = &pQuery->pExpr1[col];
 
-    sas->offset  = pQuery->pos;
-    sas->colList = pQuery->colList;
+    sas->offset    = (QUERY_IS_ASC_QUERY(pQuery)) ? pQuery->pos : pQuery->pos - (size - 1);
+    sas->colList   = pQuery->colList;
     sas->numOfCols = pQuery->numOfCols;
-    sas->data    = calloc(pQuery->numOfCols, POINTER_BYTES);
+    sas->data      = calloc(pQuery->numOfCols, POINTER_BYTES);
 
     if (sas->data == NULL) {
       longjmp(pRuntimeEnv->env, TSDB_CODE_QRY_OUT_OF_MEMORY);

From 3b92e7f49b2ddaadcfb2fd11e879214c8495b17a Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Tue, 24 Nov 2020 10:29:08 +0800
Subject: [PATCH 20/41] [TD-225] update sim test script.

---
 .../general/parser/col_arithmetic_query.sim   | 146 +++++++++++++++---
 1 file changed, 124 insertions(+), 22 deletions(-)

diff --git a/tests/script/general/parser/col_arithmetic_query.sim b/tests/script/general/parser/col_arithmetic_query.sim
index 61a48e4a80..95e0ed68d7 100644
--- a/tests/script/general/parser/col_arithmetic_query.sim
+++ b/tests/script/general/parser/col_arithmetic_query.sim
@@ -7,12 +7,12 @@ $stbPrefix = ca_stb
 $rowNum = 10000
 
 $i = 0
-$db = $dbPrefix . $i
-
 $db = $dbPrefix . $i
 sql use $db
 
 $tb = $tbPrefix . 0
+$stb = $stbPrefix . $i
+
 ## TBASE-344
 sql select c1*2 from $tb
 if $rows != $rowNum then
@@ -41,7 +41,8 @@ if $data00 != 0.000000000 then
   return -1
 endi
 
-if $data01 != NaN then
+if $data01 != -nan then
+  print expect -nan, actual: $data01
   return -1
 endi
 
@@ -67,6 +68,7 @@ if $rows != 10000 then
 endi
 
 if $data00 != 0.100000000 then
+  print expect 0.100000000, acutal:$data00
   return -1
 endi
 
@@ -92,15 +94,15 @@ if $data10 != 16.000000000 then
   return -1
 endi
 
-if $data21 != 20.250000000 then
+if $data20 != 20.250000000 then
+  print expect 20.250000000, acutal:$data21
   return -1
 endi
 
-if $data31 != 0.000000000 then
+if $data30 != 0.000000000 then
   return -1
 endi
 
-
 # no result return [d.3] ==============================================================
 sql select c1 * 91- 7 from $tb where ts < 1537146000000
 if $rows != 0 then
@@ -120,11 +122,59 @@ endi
 # not available
 
 # multi row result aggregation [d.4]
-sql select top(c1, 1) - bottom(c1, 1) from $tb
-sql select top(c1, 99) - bottom(c1, 99) from $tb
+sql_error select top(c1, 1) - bottom(c1, 1) from $tb
+sql_error select top(c1, 99) - bottom(c1, 99) from $tb
+sql_error select top(c1,1) - 88 from $tb
 
 # all data types [d.6] ================================================================
-sql select c2-c1, c3/c2, c4*c3, c5%c4, c6+99%22, c2-c2 from $tb
+sql select c2-c1*1.1, c3/c2, c4*c3, c5%c4, (c6+c4)%22, c2-c2 from $tb
+if $rows != 10000 then
+ return -1
+endi
+
+if $data00 != 0.000000000 then
+  return -1
+endi
+
+if $data01 != -nan then
+  return -1
+endi
+
+if $data02 != 0.000000000 then
+  return -1
+endi
+
+if $data03 != 0.000000000 then
+  return -1
+endi
+
+if $data04 != 0.000000000 then
+  return -1
+endi
+
+if $data05 != 0.000000000 then
+  return -1
+endi
+
+if $data90 != -0.900000000 then
+  return -1
+endi
+
+if $data91 != 1.000000000 then
+  return -1
+endi
+
+if $data92 != 81.000000000 then
+  return -1
+endi
+
+if $data93 != 0.000000000 then
+  return -1
+endi
+
+if $data94 != 18.000000000 then
+  return -1
+endi
 
 # error case, ts/bool/binary/nchar not support arithmetic expression
 sql_error select ts+ts from $tb
@@ -135,8 +185,6 @@ sql_error select c9+c8 from $tb
 sql_error select c7-c8, c9-c8 from $tb
 sql_error select ts-c9 from $tb
 sql_error select c8+c7, c9+c9+c8+c7/c6 from $tb
-sql_error select c1/0, c2/0, c3/0.0 from $tb
-sql_error select c1/0.00000000001 from $tb
 
 # arithmetic expression in join [d.7]==================================================
 
@@ -162,7 +210,7 @@ if $data00 != 93.000000000 then
   return -1
 endi
 
-if $data90 != 12.000000000 then
+if $data90 != 76.000000000 then
   return -1
 endi
 
@@ -171,27 +219,81 @@ if $rows != 1 then
   return -1
 endi
 
-if $data00 !=
+if $data00 != 0.090796283 then
+  return -1
+endi
 
 # slimit/soffset not support for normal table query. [d.11]============================
 sql_error select sum(c1) from $tb slimit 1 soffset 19;
 
 # fill [d.12]==========================================================================
-sql_error select c2-c2, c3-c4, c5%c6 from $tb fill(value, 12);
+sql_error select c2-c2, c3-c4, c5%c3 from $tb fill(value, 12);
 
 # constant column. [d.13]==============================================================
+sql select c1, c2+c6, 12.9876545678, 1, 1.1 from $tb
+if $rows != 10000 then
+  return -1
+endi
 
+if $data00 != 0 then
+  return -1
+endi
+
+if $data01 != 0.000000000 then
+  return -1
+endi
+
+if $data02 != 12.987654568 then
+  return -1
+endi
+
+if $data03 != 1 then
+  return -1
+endi
+
+if $data04 != 1.100000000 then
+  return -1
+endi
+
+if $data10 != 1 then
+  return -1
+endi
 
 # column value filter [d.14]===========================================================
+sql select c1, c2+c6, 12.9876545678, 1, 1.1 from $tb where c1<2
+if $rows != 2000 then
+  return -1
+endi
 
+if $data00 != 0 then
+  return -1
+endi
+
+if $data01 != 0.000000000 then
+  return -1
+endi
+
+if $data02 != 12.987654568 then
+  return -1
+endi
+
+if $data03 != 1 then
+  return -1
+endi
+
+if $data10 != 1 then
+  return -1
+endi
+
+if $data20 != 0 then
+  return -1
+endi
 
 # tag filter(not support for normal table). [d.15]=====================================
 sql_error select c2+99 from $tb where t1=12;
 
 # multi-field output [d.16]============================================================
-sql select count(*), sum(c1)*avg(c2), avg(c3)*count(c3), sum(c3), sum(c4), first(c7), last(c8), first(c9), first(c7), last(c8) from $tb
-
-sql select c4*1+1/2 from $tb
+sql select c4*1+1/2,c4*1+1/2,c4*1+1/2,c4*1+1/2,c4*1+1/2 from $tb
 if $rows != $rowNum then
   return -1
 endi
@@ -216,15 +318,17 @@ sql_error select c7-c9 from $tb interval(2y)
 # see test cases below
 
 # multiple retrieve [d.20]===============================================================
-sql select c2-c2 from $tb;
+sql select c2-c2, 911 from $tb
 
 #======================================= aggregation function arithmetic query cases ================
 # asc/desc order [d.2]
 sql select first(c1) * ( 2 / 3 ) from $stb order by ts asc;
 sql select (count(c1) * 2) % 7.9 from $stb order by ts desc;
 
+sql select spread(c1 )/44 from $stb order by ts asc;
+
 # all possible function in the arithmetic expressioin
-sql select min(c1) * max(c2) /4, sum(c1) * percentile(c2, 20), apercentile(c4, 33) + 52/9, spread(c5)/min(c2), xxxx, from $stb where ts <  and ts >
+sql select min(c1) * max(c2) /4, sum(c1) * percentile(c2, 20), apercentile(c4, 33) + 52/9, spread(c5)/min(c2) from $stb where ts <  and ts >
 
 # no result return [d.3]
 sql select first(c1) * 91 - 7, last(c3) from $stb where ts < 1537146000000
@@ -291,7 +395,7 @@ sql_error select c2-c2, c3-c4, c5%c6 from $tb fill(value, 12);
 
 
 # tag filter(not support for normal table). [d.15]
-sql_error select c2+99 from $tb where t1=12;
+sql_error select sum(c2)+99 from $tb where t1=12;
 
 # multi-field output [d.16]
 sql select count(*), sum(c1)*avg(c2), avg(c3)*count(c3), sum(c3), sum(c4), first(c7), last(c8), first(c9), first(c7), last(c8) from $tb
@@ -325,5 +429,3 @@ sql select c2-c2 from $tb;
 
 
 sql select first(c1)-last(c1), spread(c2), max(c3) - min(c3), avg(c4)*count(c4) from $tb
-
-

From c17d202e0c35c1a25ffcb23ef7424094fa9757d9 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Tue, 24 Nov 2020 11:00:10 +0800
Subject: [PATCH 21/41] [TD-225] fix compiler error.

---
 src/query/src/qResultbuf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/query/src/qResultbuf.c b/src/query/src/qResultbuf.c
index dfa8bcd95b..55a7aea53a 100644
--- a/src/query/src/qResultbuf.c
+++ b/src/query/src/qResultbuf.c
@@ -122,7 +122,7 @@ static char* doFlushPageToDisk(SDiskbasedResultBuf* pResultBuf, SPageInfo* pg) {
     int32_t ret = fseek(pResultBuf->file, pg->info.offset, SEEK_SET);
     assert(ret == 0);
 
-    ret = fwrite(t, 1, size, pResultBuf->file);
+    ret = (int32_t) fwrite(t, 1, size, pResultBuf->file);
     assert(ret == size);
 
     if (pResultBuf->fileSize < pg->info.offset + pg->info.length) {

From c3fd294c0b816a0e52a12ba7b9d178899997ae21 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Tue, 24 Nov 2020 12:00:17 +0800
Subject: [PATCH 22/41] [TD-225] fix bugs in regression test.

---
 src/query/inc/qUtil.h                         |  1 +
 src/query/src/qExecutor.c                     |  2 +-
 src/query/src/qUtil.c                         |  6 +++
 .../general/parser/col_arithmetic_query.sim   | 51 ++++++++++++++++++-
 4 files changed, 57 insertions(+), 3 deletions(-)

diff --git a/src/query/inc/qUtil.h b/src/query/inc/qUtil.h
index 62bf245a2b..bc23ffadd4 100644
--- a/src/query/inc/qUtil.h
+++ b/src/query/inc/qUtil.h
@@ -81,6 +81,7 @@ int32_t getNumOfAllocatedResultRows(SResultRowPool* p);
 int32_t getNumOfUsedResultRows(SResultRowPool* p);
 
 uint64_t getResultInfoUId(SQueryRuntimeEnv* pRuntimeEnv);
+bool isPointInterpoQuery(SQuery *pQuery);
 
 
 #endif  // TDENGINE_QUERYUTIL_H
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 7d6068ff64..fce25ae119 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -1825,7 +1825,7 @@ static bool isFixedOutputQuery(SQueryRuntimeEnv* pRuntimeEnv) {
 }
 
 // todo refactor with isLastRowQuery
-static bool isPointInterpoQuery(SQuery *pQuery) {
+bool isPointInterpoQuery(SQuery *pQuery) {
   for (int32_t i = 0; i < pQuery->numOfOutput; ++i) {
     int32_t functionID = pQuery->pExpr1[i].base.functionId;
     if (functionID == TSDB_FUNC_INTERP) {
diff --git a/src/query/src/qUtil.c b/src/query/src/qUtil.c
index 4b8d7ea930..2b4cdef9b0 100644
--- a/src/query/src/qUtil.c
+++ b/src/query/src/qUtil.c
@@ -388,6 +388,12 @@ uint64_t getResultInfoUId(SQueryRuntimeEnv* pRuntimeEnv) {
     return 0;  // for simple table query, the uid is always set to be 0;
   }
 
+  SQuery* pQuery = pRuntimeEnv->pQuery;
+  if ((pQuery->checkBuffer == 1 && pQuery->interval.interval == 0) || isPointInterpoQuery(pQuery) ||
+      pRuntimeEnv->groupbyNormalCol) {
+    return 0;
+  }
+
   STableId* id = TSDB_TABLEID(pRuntimeEnv->pQuery->current);
   return id->uid;
 }
\ No newline at end of file
diff --git a/tests/script/general/parser/col_arithmetic_query.sim b/tests/script/general/parser/col_arithmetic_query.sim
index 95e0ed68d7..408b039144 100644
--- a/tests/script/general/parser/col_arithmetic_query.sim
+++ b/tests/script/general/parser/col_arithmetic_query.sim
@@ -323,9 +323,56 @@ sql select c2-c2, 911 from $tb
 #======================================= aggregation function arithmetic query cases ================
 # asc/desc order [d.2]
 sql select first(c1) * ( 2 / 3 ) from $stb order by ts asc;
-sql select (count(c1) * 2) % 7.9 from $stb order by ts desc;
+if $rows != 1 then
+  return -1
+endi
 
-sql select spread(c1 )/44 from $stb order by ts asc;
+if $data00 != 0.000000000 then
+  return -1
+endi
+
+sql select first(c1) * (2/99) from $stb order by ts desc;
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 0.000000000 then
+  return -1
+endi
+
+sql select (count(c1) * 2) % 7.9, (count(c1) * 2), ( count(1)*2) from $stb order by ts desc;
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 1.800000000 then
+  return -1
+endi
+
+if $data01 != 100000 then
+  return -1
+endi
+
+if $data02 != 200000 then
+  return -1
+endi
+
+sql select spread( c1 )/44, spread(c1), 0.204545455 * 44 from $stb order by ts asc;
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 0.204545455 then
+  return -1
+endi
+
+if $data01 != 9.000000000 then
+  return -1
+endi
+
+if $data02 != 9.000000020 then
+  return -1
+endi
 
 # all possible function in the arithmetic expressioin
 sql select min(c1) * max(c2) /4, sum(c1) * percentile(c2, 20), apercentile(c4, 33) + 52/9, spread(c5)/min(c2) from $stb where ts <  and ts >

From f9c34c937068a76cde87aa719fb177749846404d Mon Sep 17 00:00:00 2001
From: liuyq-617 <yqliu@taosdata.com>
Date: Tue, 24 Nov 2020 17:27:42 +0800
Subject: [PATCH 23/41] [TD-2125][TD-2173]<feature>python connector

---
 src/connector/python/linux/python2/setup.py   |   2 +-
 .../python/linux/python2/taos/cinterface.py   | 115 ++++++++++++----
 .../python/linux/python2/taos/cursor.py       |  20 ++-
 src/connector/python/linux/python3/setup.py   |   2 +-
 .../python/linux/python3/taos/cinterface.py   | 129 ++++++++++++------
 .../python/linux/python3/taos/cursor.py       |  26 ++--
 src/connector/python/windows/python2/setup.py |   2 +-
 .../python/windows/python2/taos/cinterface.py | 118 ++++++++++++----
 .../python/windows/python2/taos/cursor.py     |  22 ++-
 src/connector/python/windows/python3/setup.py |   2 +-
 .../python/windows/python3/taos/cinterface.py | 107 ++++++++++++---
 .../python/windows/python3/taos/cursor.py     |  22 ++-
 12 files changed, 428 insertions(+), 139 deletions(-)

diff --git a/src/connector/python/linux/python2/setup.py b/src/connector/python/linux/python2/setup.py
index 2e4f80b8f0..b3daa98bdc 100644
--- a/src/connector/python/linux/python2/setup.py
+++ b/src/connector/python/linux/python2/setup.py
@@ -5,7 +5,7 @@ with open("README.md", "r") as fh:
 
 setuptools.setup(
     name="taos",
-    version="2.0.0",
+    version="2.0.2",
     author="Taosdata Inc.",
     author_email="support@taosdata.com",
     description="TDengine python client package",
diff --git a/src/connector/python/linux/python2/taos/cinterface.py b/src/connector/python/linux/python2/taos/cinterface.py
index 269326535c..6f0435722f 100644
--- a/src/connector/python/linux/python2/taos/cinterface.py
+++ b/src/connector/python/linux/python2/taos/cinterface.py
@@ -18,7 +18,7 @@ def _crow_timestamp_to_python(data, num_of_rows, nbytes=None, micro=False):
         _timestamp_converter = _convert_microsecond_to_datetime
 
     if num_of_rows > 0:
-        return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)][::1]))
+        return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)]))
     else:
         return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)]))
 
@@ -26,7 +26,7 @@ def _crow_bool_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C bool row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_bool))[:abs(num_of_rows)] ]
 
@@ -34,7 +34,7 @@ def _crow_tinyint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C tinyint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     
@@ -42,7 +42,7 @@ def _crow_smallint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C smallint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)][::1]]
+        return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)]]
     else:
         return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)] ]
 
@@ -50,7 +50,7 @@ def _crow_int_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C int row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)] ]
 
@@ -58,7 +58,7 @@ def _crow_bigint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C bigint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)] ]
 
@@ -66,7 +66,7 @@ def _crow_float_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C float row to python row
     """
     if num_of_rows > 0:
-        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)][::1] ]
+        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)] ]
     else:
         return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)] ]
 
@@ -74,7 +74,7 @@ def _crow_double_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C double row to python row
     """
     if num_of_rows > 0:
-        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)][::1] ]
+        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)] ]
     else:
         return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)] ]
 
@@ -82,7 +82,7 @@ def _crow_binary_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C binary row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)][::1]]
+        return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)]]
     else:
         return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)]]
 
@@ -90,9 +90,7 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C nchar row to python row
     """
     assert(nbytes is not None)
-
-    res = []
-
+    res=[]
     for i in range(abs(num_of_rows)):
         try:
             if num_of_rows >= 0:
@@ -103,17 +101,49 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
         except ValueError:
             res.append(None)
 
+    return res 
+
+def _crow_binary_to_python_block(data, num_of_rows, nbytes=None, micro=False):
+    """Function to convert C binary row to python row
+    """
+    res=[]
+    if num_of_rows > 0:
+        for i in range(abs(num_of_rows)):
+            try:
+                rbyte=ctypes.cast(data+nbytes*i,ctypes.POINTER(ctypes.c_short))[:1].pop()
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode()[0:rbyte] )
+            except ValueError:
+                res.append(None)
+    else:
+        for i in range(abs(num_of_rows)):
+            try:
+                rbyte=ctypes.cast(data+nbytes*i,ctypes.POINTER(ctypes.c_short))[:1].pop()
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode()[0:rbyte] )
+            except ValueError:
+                res.append(None)
+    return res
+
+def _crow_nchar_to_python_block(data, num_of_rows, nbytes=None, micro=False):
+    """Function to convert C nchar row to python row
+    """
+    assert(nbytes is not None)
+    res=[]
+    if num_of_rows >= 0:
+        for i in range(abs(num_of_rows)):
+            try:
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode() )
+            except ValueError:
+                res.append(None)
+    else:
+        for i in range(abs(num_of_rows)):
+            try:
+                res.append( (ctypes.cast(data+nbytes*i+2,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
+            except ValueError:
+                res.append(None)
     return res
-    # if num_of_rows > 0:
-    #     for i in range(abs(num_of_rows)):
-    #         try:
-    #             res.append( (ctypes.cast(data+nbytes*i,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
-    #         except ValueError:
-    #             res.append(None)
-    #     return res
-    #         # return [ele.value for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[:abs(num_of_rows)][::-1]]
-    # else:
-    #     return [ele.value for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[:abs(num_of_rows)]]
 
 _CONVERT_FUNC = {
     FieldType.C_BOOL: _crow_bool_to_python,
@@ -128,6 +158,19 @@ _CONVERT_FUNC = {
     FieldType.C_NCHAR : _crow_nchar_to_python
 }
 
+_CONVERT_FUNC_BLOCK = {
+    FieldType.C_BOOL: _crow_bool_to_python,
+    FieldType.C_TINYINT : _crow_tinyint_to_python,
+    FieldType.C_SMALLINT : _crow_smallint_to_python,
+    FieldType.C_INT : _crow_int_to_python,
+    FieldType.C_BIGINT : _crow_bigint_to_python,
+    FieldType.C_FLOAT : _crow_float_to_python,
+    FieldType.C_DOUBLE : _crow_double_to_python,
+    FieldType.C_BINARY: _crow_binary_to_python_block,
+    FieldType.C_TIMESTAMP : _crow_timestamp_to_python, 
+    FieldType.C_NCHAR : _crow_nchar_to_python_block
+}
+
 # Corresponding TAOS_FIELD structure in C
 class TaosField(ctypes.Structure):
     _fields_ = [('name', ctypes.c_char * 65),
@@ -227,8 +270,8 @@ class CTaosInterface(object):
             print('connect to TDengine failed')
             raise ConnectionError("connect to TDengine failed")
             # sys.exit(1)
-        else:
-            print('connect to TDengine success')
+        #else:
+        #    print('connect to TDengine success')
 
         return connection
 
@@ -237,7 +280,7 @@ class CTaosInterface(object):
         '''Close the TDengine handle
         '''
         CTaosInterface.libtaos.taos_close(connection)
-        print('connection is closed')
+        #print('connection is closed')
 
     @staticmethod
     def query(connection, sql):
@@ -310,6 +353,24 @@ class CTaosInterface(object):
 
     @staticmethod
     def fetchBlock(result, fields):
+        pblock = ctypes.c_void_p(0)
+        num_of_rows = CTaosInterface.libtaos.taos_fetch_block(
+            result, ctypes.byref(pblock))
+        if num_of_rows == 0:
+            return None, 0
+        isMicro = (CTaosInterface.libtaos.taos_result_precision(result) == FieldType.C_TIMESTAMP_MICRO)
+        blocks = [None] * len(fields)
+        fieldL = CTaosInterface.libtaos.taos_fetch_lengths(result)
+        fieldLen = [ele for ele in ctypes.cast(fieldL,  ctypes.POINTER(ctypes.c_int))[:len(fields)]]
+        for i in range(len(fields)):
+            data = ctypes.cast(pblock, ctypes.POINTER(ctypes.c_void_p))[i]
+            if fields[i]['type'] not in _CONVERT_FUNC_BLOCK:
+                raise DatabaseError("Invalid data type returned from database")
+            blocks[i] = _CONVERT_FUNC_BLOCK[fields[i]['type']](data, num_of_rows, fieldLen[i], isMicro)
+
+        return blocks, abs(num_of_rows)
+    @staticmethod
+    def fetchRow(result, fields):
         pblock = ctypes.c_void_p(0)
         pblock = CTaosInterface.libtaos.taos_fetch_row(result)  
         if pblock : 
@@ -393,7 +454,7 @@ class CTaosInterface(object):
     def errStr(result):
         """Return the error styring
         """
-        return CTaosInterface.libtaos.taos_errstr(result)
+        return CTaosInterface.libtaos.taos_errstr(result).decode('utf-8')
 
 
 if __name__ == '__main__':
@@ -410,4 +471,4 @@ if __name__ == '__main__':
     print(data)
 
     cinter.freeResult(result)
-    cinter.close(conn)
\ No newline at end of file
+    cinter.close(conn)
diff --git a/src/connector/python/linux/python2/taos/cursor.py b/src/connector/python/linux/python2/taos/cursor.py
index bc6670ca77..eee5e39488 100644
--- a/src/connector/python/linux/python2/taos/cursor.py
+++ b/src/connector/python/linux/python2/taos/cursor.py
@@ -49,7 +49,7 @@ class TDengineCursor(object):
             raise OperationalError("Invalid use of fetch iterator")
 
         if self._block_rows <= self._block_iter:
-            block, self._block_rows = CTaosInterface.fetchBlock(
+            block, self._block_rows = CTaosInterface.fetchRow(
                 self._result, self._fields)
             if self._block_rows == 0:
                 raise StopIteration
@@ -190,6 +190,23 @@ class TDengineCursor(object):
         if self._result is None or self._fields is None:
             raise OperationalError("Invalid use of fetchall")
 
+        buffer = [[] for i in range(len(self._fields))]
+        self._rowcount = 0
+        while True:
+            block, num_of_fields = CTaosInterface.fetchRow(self._result, self._fields)
+            errno = CTaosInterface.libtaos.taos_errno(self._result)
+            if errno != 0:
+                raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
+            if num_of_fields == 0:
+                break
+            self._rowcount += num_of_fields
+            for i in range(len(self._fields)):
+                buffer[i].extend(block[i])
+        return list(map(tuple, zip(*buffer)))
+    def fetchall_block(self):
+        if self._result is None or self._fields is None:
+            raise OperationalError("Invalid use of fetchall")
+
         buffer = [[] for i in range(len(self._fields))]
         self._rowcount = 0
         while True:
@@ -203,7 +220,6 @@ class TDengineCursor(object):
             for i in range(len(self._fields)):
                 buffer[i].extend(block[i])
         return list(map(tuple, zip(*buffer)))
-
     def nextset(self):
         """
         """
diff --git a/src/connector/python/linux/python3/setup.py b/src/connector/python/linux/python3/setup.py
index 03a49fc1c5..f49ebe2b6d 100644
--- a/src/connector/python/linux/python3/setup.py
+++ b/src/connector/python/linux/python3/setup.py
@@ -5,7 +5,7 @@ with open("README.md", "r") as fh:
 
 setuptools.setup(
     name="taos",
-    version="2.0.0",
+    version="2.0.2",
     author="Taosdata Inc.",
     author_email="support@taosdata.com",
     description="TDengine python client package",
diff --git a/src/connector/python/linux/python3/taos/cinterface.py b/src/connector/python/linux/python3/taos/cinterface.py
index be5b99d8c1..bbf5a0c714 100644
--- a/src/connector/python/linux/python3/taos/cinterface.py
+++ b/src/connector/python/linux/python3/taos/cinterface.py
@@ -18,7 +18,7 @@ def _crow_timestamp_to_python(data, num_of_rows, nbytes=None, micro=False):
         _timestamp_converter = _convert_microsecond_to_datetime
 
     if num_of_rows > 0:
-        return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)][::1]))
+        return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)]))
     else:
         return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)]))
 
@@ -26,7 +26,7 @@ def _crow_bool_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C bool row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_bool))[:abs(num_of_rows)] ]
 
@@ -34,7 +34,7 @@ def _crow_tinyint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C tinyint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     
@@ -42,7 +42,7 @@ def _crow_smallint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C smallint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)][::1]]
+        return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)]]
     else:
         return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)] ]
 
@@ -50,7 +50,7 @@ def _crow_int_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C int row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)] ]
 
@@ -58,7 +58,7 @@ def _crow_bigint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C bigint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_long))[:abs(num_of_rows)] ]
 
@@ -66,7 +66,7 @@ def _crow_float_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C float row to python row
     """
     if num_of_rows > 0:
-        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)][::1] ]
+        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)] ]
     else:
         return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)] ]
 
@@ -74,7 +74,7 @@ def _crow_double_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C double row to python row
     """
     if num_of_rows > 0:
-        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)][::1] ]
+        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)] ]
     else:
         return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)] ]
 
@@ -82,7 +82,7 @@ def _crow_binary_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C binary row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)][::1]]
+        return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)]]
     else:
         return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)]]
 
@@ -90,9 +90,7 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C nchar row to python row
     """
     assert(nbytes is not None)
-
-    res = []
-
+    res=[]
     for i in range(abs(num_of_rows)):
         try:
             if num_of_rows >= 0:
@@ -103,17 +101,49 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
         except ValueError:
             res.append(None)
 
+    return res 
+
+def _crow_binary_to_python_block(data, num_of_rows, nbytes=None, micro=False):
+    """Function to convert C binary row to python row
+    """
+    res=[]
+    if num_of_rows > 0:
+        for i in range(abs(num_of_rows)):
+            try:
+                rbyte=ctypes.cast(data+nbytes*i,ctypes.POINTER(ctypes.c_short))[:1].pop()
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode()[0:rbyte] )
+            except ValueError:
+                res.append(None)
+    else:
+        for i in range(abs(num_of_rows)):
+            try:
+                rbyte=ctypes.cast(data+nbytes*i,ctypes.POINTER(ctypes.c_short))[:1].pop()
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode()[0:rbyte] )
+            except ValueError:
+                res.append(None)
+    return res
+
+def _crow_nchar_to_python_block(data, num_of_rows, nbytes=None, micro=False):
+    """Function to convert C nchar row to python row
+    """
+    assert(nbytes is not None)
+    res=[]
+    if num_of_rows >= 0:
+        for i in range(abs(num_of_rows)):
+            try:
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode() )
+            except ValueError:
+                res.append(None)
+    else:
+        for i in range(abs(num_of_rows)):
+            try:
+                res.append( (ctypes.cast(data+nbytes*i+2,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
+            except ValueError:
+                res.append(None)
     return res
-    # if num_of_rows > 0:
-    #     for i in range(abs(num_of_rows)):
-    #         try:
-    #             res.append( (ctypes.cast(data+nbytes*i,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
-    #         except ValueError:
-    #             res.append(None)
-    #     return res
-    #         # return [ele.value for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[:abs(num_of_rows)][::1]]
-    # else:
-    #     return [ele.value for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[:abs(num_of_rows)]]
 
 _CONVERT_FUNC = {
     FieldType.C_BOOL: _crow_bool_to_python,
@@ -128,6 +158,19 @@ _CONVERT_FUNC = {
     FieldType.C_NCHAR : _crow_nchar_to_python
 }
 
+_CONVERT_FUNC_BLOCK = {
+    FieldType.C_BOOL: _crow_bool_to_python,
+    FieldType.C_TINYINT : _crow_tinyint_to_python,
+    FieldType.C_SMALLINT : _crow_smallint_to_python,
+    FieldType.C_INT : _crow_int_to_python,
+    FieldType.C_BIGINT : _crow_bigint_to_python,
+    FieldType.C_FLOAT : _crow_float_to_python,
+    FieldType.C_DOUBLE : _crow_double_to_python,
+    FieldType.C_BINARY: _crow_binary_to_python_block,
+    FieldType.C_TIMESTAMP : _crow_timestamp_to_python, 
+    FieldType.C_NCHAR : _crow_nchar_to_python_block
+}
+
 # Corresponding TAOS_FIELD structure in C
 class TaosField(ctypes.Structure):
     _fields_ = [('name', ctypes.c_char * 65),
@@ -253,7 +296,7 @@ class CTaosInterface(object):
             raise AttributeError("sql is expected as a string")
         # finally:
         #     CTaosInterface.libtaos.close(connection)
-      
+
     @staticmethod
     def affectedRows(result):
         """The affected rows after runing query
@@ -308,29 +351,26 @@ class CTaosInterface(object):
 
         return fields
 
-    # @staticmethod
-    # def fetchBlock(result, fields):
-    #     pblock = ctypes.c_void_p(0)
-    #     num_of_rows = CTaosInterface.libtaos.taos_fetch_block(
-    #         result, ctypes.byref(pblock))
-    #     if num_of_rows == 0:
-    #         return None, 0
-
-    #     isMicro = (CTaosInterface.libtaos.taos_result_precision(result) == FieldType.C_TIMESTAMP_MICRO)
-    #     blocks = [None] * len(fields)
-    #     fieldL = CTaosInterface.libtaos.taos_fetch_lengths(result)
-    #     fieldLen = [ele for ele in ctypes.cast(fieldL,  ctypes.POINTER(ctypes.c_int))[:len(fields)]]
-    #     for i in range(len(fields)):
-    #         data = ctypes.cast(pblock, ctypes.POINTER(ctypes.c_void_p))[i]
-
-    #         if fields[i]['type'] not in _CONVERT_FUNC:
-    #             raise DatabaseError("Invalid data type returned from database")
-    #         print('====================',fieldLen[i])
-    #         blocks[i] = _CONVERT_FUNC[fields[i]['type']](data, num_of_rows, fieldLen[i], isMicro)
-
-    #     return blocks, abs(num_of_rows)
     @staticmethod
     def fetchBlock(result, fields):
+        pblock = ctypes.c_void_p(0)
+        num_of_rows = CTaosInterface.libtaos.taos_fetch_block(
+            result, ctypes.byref(pblock))
+        if num_of_rows == 0:
+            return None, 0
+        isMicro = (CTaosInterface.libtaos.taos_result_precision(result) == FieldType.C_TIMESTAMP_MICRO)
+        blocks = [None] * len(fields)
+        fieldL = CTaosInterface.libtaos.taos_fetch_lengths(result)
+        fieldLen = [ele for ele in ctypes.cast(fieldL,  ctypes.POINTER(ctypes.c_int))[:len(fields)]]
+        for i in range(len(fields)):
+            data = ctypes.cast(pblock, ctypes.POINTER(ctypes.c_void_p))[i]
+            if fields[i]['type'] not in _CONVERT_FUNC_BLOCK:
+                raise DatabaseError("Invalid data type returned from database")
+            blocks[i] = _CONVERT_FUNC_BLOCK[fields[i]['type']](data, num_of_rows, fieldLen[i], isMicro)
+
+        return blocks, abs(num_of_rows)
+    @staticmethod
+    def fetchRow(result, fields):
         pblock = ctypes.c_void_p(0)
         pblock = CTaosInterface.libtaos.taos_fetch_row(result)  
         if pblock : 
@@ -350,6 +390,7 @@ class CTaosInterface(object):
         else:
             return None, 0
         return blocks, abs(num_of_rows)
+
     @staticmethod
     def freeResult(result):
         CTaosInterface.libtaos.taos_free_result(result)
diff --git a/src/connector/python/linux/python3/taos/cursor.py b/src/connector/python/linux/python3/taos/cursor.py
index eb10bed485..d8184668c8 100644
--- a/src/connector/python/linux/python3/taos/cursor.py
+++ b/src/connector/python/linux/python3/taos/cursor.py
@@ -5,7 +5,6 @@ import threading
 
 # querySeqNum = 0
 
-
 class TDengineCursor(object):
     """Database cursor which is used to manage the context of a fetch operation.
 
@@ -51,7 +50,7 @@ class TDengineCursor(object):
             raise OperationalError("Invalid use of fetch iterator")
 
         if self._block_rows <= self._block_iter:
-            block, self._block_rows = CTaosInterface.fetchBlock(
+            block, self._block_rows = CTaosInterface.fetchRow(
                 self._result, self._fields)
             if self._block_rows == 0:
                 raise StopIteration
@@ -196,18 +195,13 @@ class TDengineCursor(object):
     def fetchall(self):
         """Fetch all (remaining) rows of a query result, returning them as a sequence of sequences (e.g. a list of tuples). Note that the cursor's arraysize attribute can affect the performance of this operation.
         """
-        # if threading.get_ident() != self._threadId:
-        #     info ="[WARNING] Cursor fetchall:Thread ID not match,creater:"+str(self._threadId)+" caller:"+str(threading.get_ident())
-        #     raise OperationalError(info)
-            # print(info)
-            # return None
         if self._result is None or self._fields is None:
             raise OperationalError("Invalid use of fetchall")
 
         buffer = [[] for i in range(len(self._fields))]
         self._rowcount = 0
         while True:
-            block, num_of_fields = CTaosInterface.fetchBlock(self._result, self._fields)
+            block, num_of_fields = CTaosInterface.fetchRow(self._result, self._fields)
             errno = CTaosInterface.libtaos.taos_errno(self._result)
             if errno != 0:
                 raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
@@ -218,6 +212,22 @@ class TDengineCursor(object):
                 buffer[i].extend(block[i])
         return list(map(tuple, zip(*buffer)))
 
+    def fetchall_block(self):
+        if self._result is None or self._fields is None:
+            raise OperationalError("Invalid use of fetchall")
+
+        buffer = [[] for i in range(len(self._fields))]
+        self._rowcount = 0
+        while True:
+            block, num_of_fields = CTaosInterface.fetchBlock(self._result, self._fields)
+            errno = CTaosInterface.libtaos.taos_errno(self._result)
+            if errno != 0:
+                raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
+            if num_of_fields == 0: break
+            self._rowcount += num_of_fields
+            for i in range(len(self._fields)):
+                buffer[i].extend(block[i])
+        return list(map(tuple, zip(*buffer)))
     def nextset(self):
         """
         """
diff --git a/src/connector/python/windows/python2/setup.py b/src/connector/python/windows/python2/setup.py
index fd82a55650..34cb7a04d7 100644
--- a/src/connector/python/windows/python2/setup.py
+++ b/src/connector/python/windows/python2/setup.py
@@ -5,7 +5,7 @@ with open("README.md", "r") as fh:
 
 setuptools.setup(
     name="taos",
-    version="2.0.0",
+    version="2.0.2",
     author="Taosdata Inc.",
     author_email="support@taosdata.com",
     description="TDengine python client package",
diff --git a/src/connector/python/windows/python2/taos/cinterface.py b/src/connector/python/windows/python2/taos/cinterface.py
index 084d38e41c..d4bf1a0350 100644
--- a/src/connector/python/windows/python2/taos/cinterface.py
+++ b/src/connector/python/windows/python2/taos/cinterface.py
@@ -18,7 +18,7 @@ def _crow_timestamp_to_python(data, num_of_rows, nbytes=None, micro=False):
         _timestamp_converter = _convert_microsecond_to_datetime
 
     if num_of_rows > 0:
-        return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)][::1]))
+        return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)]))
     else:
         return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)]))
 
@@ -26,7 +26,7 @@ def _crow_bool_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C bool row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_bool))[:abs(num_of_rows)] ]
 
@@ -34,7 +34,7 @@ def _crow_tinyint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C tinyint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     
@@ -42,7 +42,7 @@ def _crow_smallint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C smallint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)][::1]]
+        return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)]]
     else:
         return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)] ]
 
@@ -50,7 +50,7 @@ def _crow_int_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C int row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)] ]
 
@@ -58,7 +58,7 @@ def _crow_bigint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C bigint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)] ]
 
@@ -66,7 +66,7 @@ def _crow_float_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C float row to python row
     """
     if num_of_rows > 0:
-        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)][::1] ]
+        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)] ]
     else:
         return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)] ]
 
@@ -74,7 +74,7 @@ def _crow_double_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C double row to python row
     """
     if num_of_rows > 0:
-        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)][::1] ]
+        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)] ]
     else:
         return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)] ]
 
@@ -82,7 +82,7 @@ def _crow_binary_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C binary row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)][::1]]
+        return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)]]
     else:
         return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)]]
 
@@ -90,9 +90,7 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C nchar row to python row
     """
     assert(nbytes is not None)
-
-    res = []
-
+    res=[]
     for i in range(abs(num_of_rows)):
         try:
             if num_of_rows >= 0:
@@ -103,17 +101,49 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
         except ValueError:
             res.append(None)
 
+    return res 
+
+def _crow_binary_to_python_block(data, num_of_rows, nbytes=None, micro=False):
+    """Function to convert C binary row to python row
+    """
+    res=[]
+    if num_of_rows > 0:
+        for i in range(abs(num_of_rows)):
+            try:
+                rbyte=ctypes.cast(data+nbytes*i,ctypes.POINTER(ctypes.c_short))[:1].pop()
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode()[0:rbyte] )
+            except ValueError:
+                res.append(None)
+    else:
+        for i in range(abs(num_of_rows)):
+            try:
+                rbyte=ctypes.cast(data+nbytes*i,ctypes.POINTER(ctypes.c_short))[:1].pop()
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode()[0:rbyte] )
+            except ValueError:
+                res.append(None)
+    return res
+
+def _crow_nchar_to_python_block(data, num_of_rows, nbytes=None, micro=False):
+    """Function to convert C nchar row to python row
+    """
+    assert(nbytes is not None)
+    res=[]
+    if num_of_rows >= 0:
+        for i in range(abs(num_of_rows)):
+            try:
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode() )
+            except ValueError:
+                res.append(None)
+    else:
+        for i in range(abs(num_of_rows)):
+            try:
+                res.append( (ctypes.cast(data+nbytes*i+2,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
+            except ValueError:
+                res.append(None)
     return res
-    # if num_of_rows > 0:
-    #     for i in range(abs(num_of_rows)):
-    #         try:
-    #             res.append( (ctypes.cast(data+nbytes*i,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
-    #         except ValueError:
-    #             res.append(None)
-    #     return res
-    #         # return [ele.value for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[:abs(num_of_rows)][::-1]]
-    # else:
-    #     return [ele.value for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[:abs(num_of_rows)]]
 
 _CONVERT_FUNC = {
     FieldType.C_BOOL: _crow_bool_to_python,
@@ -128,6 +158,19 @@ _CONVERT_FUNC = {
     FieldType.C_NCHAR : _crow_nchar_to_python
 }
 
+_CONVERT_FUNC_BLOCK = {
+    FieldType.C_BOOL: _crow_bool_to_python,
+    FieldType.C_TINYINT : _crow_tinyint_to_python,
+    FieldType.C_SMALLINT : _crow_smallint_to_python,
+    FieldType.C_INT : _crow_int_to_python,
+    FieldType.C_BIGINT : _crow_bigint_to_python,
+    FieldType.C_FLOAT : _crow_float_to_python,
+    FieldType.C_DOUBLE : _crow_double_to_python,
+    FieldType.C_BINARY: _crow_binary_to_python_block,
+    FieldType.C_TIMESTAMP : _crow_timestamp_to_python, 
+    FieldType.C_NCHAR : _crow_nchar_to_python_block
+}
+
 # Corresponding TAOS_FIELD structure in C
 class TaosField(ctypes.Structure):
     _fields_ = [('name', ctypes.c_char * 65),
@@ -225,9 +268,10 @@ class CTaosInterface(object):
 
         if connection.value == None:
             print('connect to TDengine failed')
+            raise ConnectionError("connect to TDengine failed")
             # sys.exit(1)
-        else:
-            print('connect to TDengine success')
+        #else:
+        #    print('connect to TDengine success')
 
         return connection
 
@@ -236,7 +280,7 @@ class CTaosInterface(object):
         '''Close the TDengine handle
         '''
         CTaosInterface.libtaos.taos_close(connection)
-        print('connection is closed')
+        #print('connection is closed')
 
     @staticmethod
     def query(connection, sql):
@@ -252,7 +296,7 @@ class CTaosInterface(object):
             raise AttributeError("sql is expected as a string")
         # finally:
         #     CTaosInterface.libtaos.close(connection)
-
+      
     @staticmethod
     def affectedRows(result):
         """The affected rows after runing query
@@ -309,6 +353,24 @@ class CTaosInterface(object):
 
     @staticmethod
     def fetchBlock(result, fields):
+        pblock = ctypes.c_void_p(0)
+        num_of_rows = CTaosInterface.libtaos.taos_fetch_block(
+            result, ctypes.byref(pblock))
+        if num_of_rows == 0:
+            return None, 0
+        isMicro = (CTaosInterface.libtaos.taos_result_precision(result) == FieldType.C_TIMESTAMP_MICRO)
+        blocks = [None] * len(fields)
+        fieldL = CTaosInterface.libtaos.taos_fetch_lengths(result)
+        fieldLen = [ele for ele in ctypes.cast(fieldL,  ctypes.POINTER(ctypes.c_int))[:len(fields)]]
+        for i in range(len(fields)):
+            data = ctypes.cast(pblock, ctypes.POINTER(ctypes.c_void_p))[i]
+            if fields[i]['type'] not in _CONVERT_FUNC_BLOCK:
+                raise DatabaseError("Invalid data type returned from database")
+            blocks[i] = _CONVERT_FUNC_BLOCK[fields[i]['type']](data, num_of_rows, fieldLen[i], isMicro)
+
+        return blocks, abs(num_of_rows)
+    @staticmethod
+    def fetchRow(result, fields):
         pblock = ctypes.c_void_p(0)
         pblock = CTaosInterface.libtaos.taos_fetch_row(result)  
         if pblock : 
@@ -393,7 +455,7 @@ class CTaosInterface(object):
     def errStr(result):
         """Return the error styring
         """
-        return CTaosInterface.libtaos.taos_errstr(result)
+        return CTaosInterface.libtaos.taos_errstr(result).decode('utf-8')
 
 
 if __name__ == '__main__':
@@ -410,4 +472,4 @@ if __name__ == '__main__':
     print(data)
 
     cinter.freeResult(result)
-    cinter.close(conn)
\ No newline at end of file
+    cinter.close(conn)
diff --git a/src/connector/python/windows/python2/taos/cursor.py b/src/connector/python/windows/python2/taos/cursor.py
index 35846cbe11..71651afee1 100644
--- a/src/connector/python/windows/python2/taos/cursor.py
+++ b/src/connector/python/windows/python2/taos/cursor.py
@@ -50,7 +50,7 @@ class TDengineCursor(object):
             raise OperationalError("Invalid use of fetch iterator")
 
         if self._block_rows <= self._block_iter:
-            block, self._block_rows = CTaosInterface.fetchBlock(self._result, self._fields)
+            block, self._block_rows = CTaosInterface.fetchRow(self._result, self._fields)
             if self._block_rows == 0:
                 raise StopIteration
             self._block = list(map(tuple, zip(*block)))
@@ -143,7 +143,25 @@ class TDengineCursor(object):
         """
         if self._result is None or self._fields is None:
             raise OperationalError("Invalid use of fetchall")
+
+        buffer = [[] for i in range(len(self._fields))]
+        self._rowcount = 0
+        while True:
+            block, num_of_fields = CTaosInterface.fetchRow(self._result, self._fields)
+            errno = CTaosInterface.libtaos.taos_errno(self._result)
+            if errno != 0:
+                raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
+            if num_of_fields == 0:
+                break
+            self._rowcount += num_of_fields
+            for i in range(len(self._fields)):
+                buffer[i].extend(block[i])
+        return list(map(tuple, zip(*buffer)))
         
+    def fetchall_block(self):
+        if self._result is None or self._fields is None:
+            raise OperationalError("Invalid use of fetchall")
+
         buffer = [[] for i in range(len(self._fields))]
         self._rowcount = 0
         while True:
@@ -178,7 +196,7 @@ class TDengineCursor(object):
         self._description = None
         self._rowcount = -1
         if self._result is not None:
-            CTaosInterface.freeResult(self._result)        
+            CTaosInterface.freeResult(self._result)
         self._result = None
         self._fields = None
         self._block = None
diff --git a/src/connector/python/windows/python3/setup.py b/src/connector/python/windows/python3/setup.py
index 9abdace5a9..c09644d330 100644
--- a/src/connector/python/windows/python3/setup.py
+++ b/src/connector/python/windows/python3/setup.py
@@ -5,7 +5,7 @@ with open("README.md", "r") as fh:
 
 setuptools.setup(
     name="taos",
-    version="2.0.0",
+    version="2.0.2",
     author="Taosdata Inc.",
     author_email="support@taosdata.com",
     description="TDengine python client package",
diff --git a/src/connector/python/windows/python3/taos/cinterface.py b/src/connector/python/windows/python3/taos/cinterface.py
index 68adf191c9..fb1b65fc15 100644
--- a/src/connector/python/windows/python3/taos/cinterface.py
+++ b/src/connector/python/windows/python3/taos/cinterface.py
@@ -18,7 +18,7 @@ def _crow_timestamp_to_python(data, num_of_rows, nbytes=None, micro=False):
         _timestamp_converter = _convert_microsecond_to_datetime
 
     if num_of_rows > 0:
-        return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)][::1]))
+        return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)]))
     else:
         return list(map(_timestamp_converter, ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)]))
 
@@ -26,7 +26,7 @@ def _crow_bool_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C bool row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_BOOL_NULL else bool(ele) for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_bool))[:abs(num_of_rows)] ]
 
@@ -34,7 +34,7 @@ def _crow_tinyint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C tinyint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_TINYINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_byte))[:abs(num_of_rows)] ]
     
@@ -42,7 +42,7 @@ def _crow_smallint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C smallint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)][::1]]
+        return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)]]
     else:
         return [ None if ele == FieldType.C_SMALLINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_short))[:abs(num_of_rows)] ]
 
@@ -50,7 +50,7 @@ def _crow_int_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C int row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_INT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_int))[:abs(num_of_rows)] ]
 
@@ -58,7 +58,7 @@ def _crow_bigint_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C bigint row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)][::1] ]
+        return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)] ]
     else:
         return [ None if ele == FieldType.C_BIGINT_NULL else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_longlong))[:abs(num_of_rows)] ]
 
@@ -66,7 +66,7 @@ def _crow_float_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C float row to python row
     """
     if num_of_rows > 0:
-        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)][::1] ]
+        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)] ]
     else:
         return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_float))[:abs(num_of_rows)] ]
 
@@ -74,7 +74,7 @@ def _crow_double_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C double row to python row
     """
     if num_of_rows > 0:
-        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)][::1] ]
+        return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)] ]
     else:
         return [ None if math.isnan(ele) else ele for ele in ctypes.cast(data,  ctypes.POINTER(ctypes.c_double))[:abs(num_of_rows)] ]
 
@@ -82,7 +82,7 @@ def _crow_binary_to_python(data, num_of_rows, nbytes=None, micro=False):
     """Function to convert C binary row to python row
     """
     if num_of_rows > 0:
-        return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)][::1]]
+        return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)]]
     else:
         return [ None if ele.value[0:1] == FieldType.C_BINARY_NULL else ele.value.decode('utf-8') for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_char * nbytes)))[:abs(num_of_rows)]]
 
@@ -104,16 +104,48 @@ def _crow_nchar_to_python(data, num_of_rows, nbytes=None, micro=False):
             res.append(None)
 
     return res
-    # if num_of_rows > 0:
-    #     for i in range(abs(num_of_rows)):
-    #         try:
-    #             res.append( (ctypes.cast(data+nbytes*i,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
-    #         except ValueError:
-    #             res.append(None)
-    #     return res
-    #         # return [ele.value for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[:abs(num_of_rows)][::-1]]
-    # else:
-    #     return [ele.value for ele in (ctypes.cast(data,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[:abs(num_of_rows)]]
+    
+def _crow_binary_to_python_block(data, num_of_rows, nbytes=None, micro=False):
+    """Function to convert C binary row to python row
+    """
+    res=[]
+    if num_of_rows > 0:
+        for i in range(abs(num_of_rows)):
+            try:
+                rbyte=ctypes.cast(data+nbytes*i,ctypes.POINTER(ctypes.c_short))[:1].pop()
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode()[0:rbyte] )
+            except ValueError:
+                res.append(None)
+    else:
+        for i in range(abs(num_of_rows)):
+            try:
+                rbyte=ctypes.cast(data+nbytes*i,ctypes.POINTER(ctypes.c_short))[:1].pop()
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode()[0:rbyte] )
+            except ValueError:
+                res.append(None)
+    return res
+
+def _crow_nchar_to_python_block(data, num_of_rows, nbytes=None, micro=False):
+    """Function to convert C nchar row to python row
+    """
+    assert(nbytes is not None)
+    res=[]
+    if num_of_rows >= 0:
+        for i in range(abs(num_of_rows)):
+            try:
+                tmpstr = ctypes.c_char_p(data+nbytes*i+2)
+                res.append( tmpstr.value.decode() )
+            except ValueError:
+                res.append(None)
+    else:
+        for i in range(abs(num_of_rows)):
+            try:
+                res.append( (ctypes.cast(data+nbytes*i+2,  ctypes.POINTER(ctypes.c_wchar * (nbytes//4))))[0].value )
+            except ValueError:
+                res.append(None)
+    return res
 
 _CONVERT_FUNC = {
     FieldType.C_BOOL: _crow_bool_to_python,
@@ -128,6 +160,19 @@ _CONVERT_FUNC = {
     FieldType.C_NCHAR : _crow_nchar_to_python
 }
 
+_CONVERT_FUNC_BLOCK = {
+    FieldType.C_BOOL: _crow_bool_to_python,
+    FieldType.C_TINYINT : _crow_tinyint_to_python,
+    FieldType.C_SMALLINT : _crow_smallint_to_python,
+    FieldType.C_INT : _crow_int_to_python,
+    FieldType.C_BIGINT : _crow_bigint_to_python,
+    FieldType.C_FLOAT : _crow_float_to_python,
+    FieldType.C_DOUBLE : _crow_double_to_python,
+    FieldType.C_BINARY: _crow_binary_to_python_block,
+    FieldType.C_TIMESTAMP : _crow_timestamp_to_python, 
+    FieldType.C_NCHAR : _crow_nchar_to_python_block
+}
+
 # Corresponding TAOS_FIELD structure in C
 class TaosField(ctypes.Structure):
     _fields_ = [('name', ctypes.c_char * 65),
@@ -227,8 +272,8 @@ class CTaosInterface(object):
             print('connect to TDengine failed')
             raise ConnectionError("connect to TDengine failed")
             # sys.exit(1)
-        else:
-            print('connect to TDengine success')
+        #else:
+        #    print('connect to TDengine success')
 
         return connection
 
@@ -237,7 +282,7 @@ class CTaosInterface(object):
         '''Close the TDengine handle
         '''
         CTaosInterface.libtaos.taos_close(connection)
-        print('connection is closed')
+        #print('connection is closed')
 
     @staticmethod
     def query(connection, sql):
@@ -310,6 +355,24 @@ class CTaosInterface(object):
 
     @staticmethod
     def fetchBlock(result, fields):
+        pblock = ctypes.c_void_p(0)
+        num_of_rows = CTaosInterface.libtaos.taos_fetch_block(
+            result, ctypes.byref(pblock))
+        if num_of_rows == 0:
+            return None, 0
+        isMicro = (CTaosInterface.libtaos.taos_result_precision(result) == FieldType.C_TIMESTAMP_MICRO)
+        blocks = [None] * len(fields)
+        fieldL = CTaosInterface.libtaos.taos_fetch_lengths(result)
+        fieldLen = [ele for ele in ctypes.cast(fieldL,  ctypes.POINTER(ctypes.c_int))[:len(fields)]]
+        for i in range(len(fields)):
+            data = ctypes.cast(pblock, ctypes.POINTER(ctypes.c_void_p))[i]
+            if fields[i]['type'] not in _CONVERT_FUNC_BLOCK:
+                raise DatabaseError("Invalid data type returned from database")
+            blocks[i] = _CONVERT_FUNC_BLOCK[fields[i]['type']](data, num_of_rows, fieldLen[i], isMicro)
+
+        return blocks, abs(num_of_rows)
+    @staticmethod
+    def fetchRow(result, fields):
         pblock = ctypes.c_void_p(0)
         pblock = CTaosInterface.libtaos.taos_fetch_row(result)  
         if pblock : 
diff --git a/src/connector/python/windows/python3/taos/cursor.py b/src/connector/python/windows/python3/taos/cursor.py
index b58b494cad..b813bba357 100644
--- a/src/connector/python/windows/python3/taos/cursor.py
+++ b/src/connector/python/windows/python3/taos/cursor.py
@@ -51,7 +51,7 @@ class TDengineCursor(object):
             raise OperationalError("Invalid use of fetch iterator")
 
         if self._block_rows <= self._block_iter:
-            block, self._block_rows = CTaosInterface.fetchBlock(self._result, self._fields)
+            block, self._block_rows = CTaosInterface.fetchRow(self._result, self._fields)
             if self._block_rows == 0:
                 raise StopIteration
             self._block = list(map(tuple, zip(*block)))
@@ -144,7 +144,25 @@ class TDengineCursor(object):
         """
         if self._result is None or self._fields is None:
             raise OperationalError("Invalid use of fetchall")
-        
+
+        buffer = [[] for i in range(len(self._fields))]
+        self._rowcount = 0
+        while True:
+            block, num_of_fields = CTaosInterface.fetchRow(self._result, self._fields)
+            errno = CTaosInterface.libtaos.taos_errno(self._result)
+            if errno != 0:
+                raise ProgrammingError(CTaosInterface.errStr(self._result), errno)
+            if num_of_fields == 0:
+                break
+            self._rowcount += num_of_fields
+            for i in range(len(self._fields)):
+                buffer[i].extend(block[i])
+        return list(map(tuple, zip(*buffer)))
+
+    def fetchall_block(self):
+        if self._result is None or self._fields is None:
+            raise OperationalError("Invalid use of fetchall")
+
         buffer = [[] for i in range(len(self._fields))]
         self._rowcount = 0
         while True:

From 19dedc226accda1655633aa1dd66d5ed47282445 Mon Sep 17 00:00:00 2001
From: zyyang <zyyang@taosdata.com>
Date: Tue, 24 Nov 2020 18:34:02 +0800
Subject: [PATCH 24/41] [TD-2132]<test>: add memory leak test case

---
 .../jdbc/cases/AppMemoryLeakTest.java         | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/AppMemoryLeakTest.java

diff --git a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/AppMemoryLeakTest.java b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/AppMemoryLeakTest.java
new file mode 100644
index 0000000000..8a3dbb2bc1
--- /dev/null
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/AppMemoryLeakTest.java
@@ -0,0 +1,23 @@
+package com.taosdata.jdbc.cases;
+
+import org.junit.Test;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+public class AppMemoryLeakTest {
+
+    @Test
+    public void testAppMemoryLeak() {
+        try {
+            Class.forName("com.taosdata.jdbc.TSDBDriver");
+
+            while (true) {
+                DriverManager.getConnection("jdbc:TAOS://localhost:6030/?user=root&password=taosdata");
+            }
+        } catch (ClassNotFoundException | SQLException e) {
+            e.printStackTrace();
+        }
+    }
+}

From 0e88426c7f864a678095ab761870d55a49cb7eb7 Mon Sep 17 00:00:00 2001
From: Ping Xiao <pxiao@taosdata.com>
Date: Wed, 25 Nov 2020 11:19:15 +0800
Subject: [PATCH 25/41] [TD-2152] <test> add test case for join query

---
 tests/pytest/insert/restfulInsert.py   |  7 +++++--
 tests/pytest/query/filterOtherTypes.py | 18 ++++++------------
 tests/pytest/query/queryJoin.py        |  2 ++
 3 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/tests/pytest/insert/restfulInsert.py b/tests/pytest/insert/restfulInsert.py
index 9fa1f33a24..c39d1cbe48 100644
--- a/tests/pytest/insert/restfulInsert.py
+++ b/tests/pytest/insert/restfulInsert.py
@@ -55,9 +55,12 @@ class RestfulInsert:
     def insertUnlimitedData(self, threadID):        
         print("thread %d started" % threadID)
         tablesPerThread = int (self.numOfTables / self.numOfThreads)
+        
+        count = 0
         while True:
             i = 0
-            start = self.ts
+            start = self.ts  + count * self.batchSize          
+            count = count + 1            
             
             for i in range(tablesPerThread):
                 tableID = i + threadID * tablesPerThread
@@ -65,7 +68,7 @@ class RestfulInsert:
                 data = "insert into %s.%s%d values" % (self.dbname, self.tableNamePerfix, tableID)
                 values = []
                 for k in range(self.batchSize):
-                    values.append("(%d, %d, %d, %d)" %  (start + j * self.batchSize + k, random.randint(1, 100), random.randint(1, 100), random.randint(1, 100)))
+                    values.append("(%d, %d, %d, %d)" %  (start + k, random.randint(1, 100), random.randint(1, 100), random.randint(1, 100)))
                 
                 if(self.outOfOrder == False):
                     for k in range(len(values)):            
diff --git a/tests/pytest/query/filterOtherTypes.py b/tests/pytest/query/filterOtherTypes.py
index 85d5a67bef..f80552138d 100644
--- a/tests/pytest/query/filterOtherTypes.py
+++ b/tests/pytest/query/filterOtherTypes.py
@@ -376,11 +376,9 @@ class TDTestCase:
         tdSql.execute("insert into t1 values(1538548685000, 1) (1538548685001, 2) (1538548685002, 3)")
         tdSql.execute("insert into t2 values(1538548685000, 4) (1538548685001, 5) (1538548685002, 6)")
 
-        tdSql.query("select * from t1 where tag1 like '%g'")
-        tdSql.checkRows(3)
+        tdSql.error("select * from t1 where tag1 like '%g'")        
 
-        tdSql.query("select * from t2 where tag1 like '%g'")
-        tdSql.checkRows(3)
+        tdSql.error("select * from t2 where tag1 like '%g'") 
 
         tdSql.query("select * from meters where tag1 like '%g'")
         tdSql.checkRows(6)
@@ -396,20 +394,16 @@ class TDTestCase:
         tdSql.execute("insert into t5 values(1538548685000, 1) (1538548685001, 2) (1538548685002, 3)")
         tdSql.execute("insert into t6 values(1538548685000, 1) (1538548685001, 2) (1538548685002, 3)")
 
-        tdSql.query("select * from t3 where tag1 like '%京'")
-        tdSql.checkRows(3)
+        tdSql.error("select * from t3 where tag1 like '%京'")        
 
-        tdSql.query("select * from t4 where tag1 like '%京'")
-        tdSql.checkRows(3)
+        tdSql.error("select * from t4 where tag1 like '%京'")        
 
         tdSql.query("select * from meters1 where tag1 like '%京'")
         tdSql.checkRows(6)
         
-        tdSql.query("select * from t5 where tag1 like '%g'")
-        tdSql.checkRows(3)
+        tdSql.error("select * from t5 where tag1 like '%g'")        
 
-        tdSql.query("select * from t6 where tag1 like '%g'")
-        tdSql.checkRows(3)
+        tdSql.error("select * from t6 where tag1 like '%g'")        
 
         tdSql.query("select * from meters1 where tag1 like '%g'")
         tdSql.checkRows(6)
diff --git a/tests/pytest/query/queryJoin.py b/tests/pytest/query/queryJoin.py
index 57b7e8868d..59e01615b4 100644
--- a/tests/pytest/query/queryJoin.py
+++ b/tests/pytest/query/queryJoin.py
@@ -175,6 +175,8 @@ class TDTestCase:
         tdSql.error("select count(join_mt0.c1), first(join_mt0.c1)-first(join_mt1.c1), first(join_mt1.c9) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts")
         tdSql.error("select count(join_mt0.c1), first(join_mt0.c1), first(join_mt1.c9) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2 order by join_mt0.t1 desc slimit 3")
         tdSql.error("select count(join_mt0.c1), first(join_mt0.c1) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2, join_mt1.t1 order by join_mt0.ts desc, join_mt1.ts asc limit 10;")
+        tdSql.error("select join_mt1.c1,join_mt0.c1 from join_mt1,join_mt0 where join_mt1.ts = join_mt0.ts and join_mt1.t1 = join_mt0.t1 order by t")
+
 
     def stop(self):
         tdSql.close()

From 092c9de4aa994bd1d15f23e02591407a6bd25edc Mon Sep 17 00:00:00 2001
From: liuyq-617 <yqliu@taosdata.com>
Date: Wed, 25 Nov 2020 15:14:01 +0800
Subject: [PATCH 26/41] [TD-2218]<test>add test case

---
 tests/pytest/fulltest.sh      |  1 +
 tests/pytest/query/bug2218.py | 54 +++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+)
 create mode 100644 tests/pytest/query/bug2218.py

diff --git a/tests/pytest/fulltest.sh b/tests/pytest/fulltest.sh
index 525fbad6c1..8977d96df4 100755
--- a/tests/pytest/fulltest.sh
+++ b/tests/pytest/fulltest.sh
@@ -158,6 +158,7 @@ python3 ./test.py -f query/bug1471.py
 python3 ./test.py -f query/bug1874.py
 python3 ./test.py -f query/bug1875.py
 python3 ./test.py -f query/bug1876.py
+python3 ./test.py -f query/bug2218.py 
 
 #stream
 python3 ./test.py -f stream/metric_1.py
diff --git a/tests/pytest/query/bug2218.py b/tests/pytest/query/bug2218.py
new file mode 100644
index 0000000000..bb92e5d9ce
--- /dev/null
+++ b/tests/pytest/query/bug2218.py
@@ -0,0 +1,54 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+from util.log import *
+from util.cases import *
+from util.sql import *
+from util.dnodes import *
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+
+    def run(self):
+        tdSql.prepare()
+        print("==========step1")
+        print("create table && insert data")
+        
+        tdSql.execute("create table mt0 (ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool)")
+        insertRows = 1000
+        t0 = 1604298064000
+        tdLog.info("insert %d rows" % (insertRows))
+        for i in range(insertRows):
+            ret = tdSql.execute(
+                "insert into mt0 values (%d , %d,%d,%d,%d,%d,%d,%d)" %
+                (t0+i,i%100,i/2,i%100,i%100,i%100,i*1.0,i%2))
+        print("==========step2")
+        print("test col*1*1 desc ")
+        tdSql.query('select c1,c1*1*1,c2*1*1,c3*1*1,c4*1*1,c5*1*1,c6*1*1 from mt0 order by ts  desc limit 2')
+        tdSql.checkData(0,0,99)
+        tdSql.checkData(0,1,0.0)
+        tdSql.checkData(0,2,0.0)
+        tdSql.checkData(0,3,0.0)
+        tdSql.checkData(0,4,0.0)
+        tdSql.checkData(0,5,0.0)
+        tdSql.checkData(0,6,0.0)
+
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file

From 3e7c81eafbcd57880ea2f4ac799858b753a02391 Mon Sep 17 00:00:00 2001
From: Ping Xiao <pxiao@taosdata.com>
Date: Wed, 25 Nov 2020 16:03:43 +0800
Subject: [PATCH 27/41] [TD-2126] <test> add test case for taosdump

---
 tests/pytest/tools/taosdumpTest.py | 89 ++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)
 create mode 100644 tests/pytest/tools/taosdumpTest.py

diff --git a/tests/pytest/tools/taosdumpTest.py b/tests/pytest/tools/taosdumpTest.py
new file mode 100644
index 0000000000..534a477b34
--- /dev/null
+++ b/tests/pytest/tools/taosdumpTest.py
@@ -0,0 +1,89 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import os
+from util.log import *
+from util.cases import *
+from util.sql import *
+from util.dnodes import *
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+        
+        self.ts = 1538548685000
+        self.numberOfTables = 10000
+        self.numberOfRecords = 100
+    
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute("create table st(ts timestamp, c1 int, c2 nchar(10)) tags(t1 int, t2 binary(10))")
+        tdSql.execute("create table t1 using st tags(1, 'beijing')")        
+        sql = "insert into t1 values"
+        currts = self.ts
+        for i in range(100):
+            sql += "(%d, %d, 'nchar%d')" % (currts + i, i % 100, i % 100)
+        tdSql.execute(sql)
+
+        tdSql.execute("create table t2 using st tags(2, 'shanghai')")        
+        sql = "insert into t2 values"
+        currts = self.ts
+        for i in range(100):
+            sql += "(%d, %d, 'nchar%d')" % (currts + i, i % 100, i % 100)
+        tdSql.execute(sql)
+
+        os.system("taosdump --databases db -o /tmp")
+        
+        tdSql.execute("drop database db")
+        tdSql.query("show databases")
+        tdSql.checkRows(0)
+        
+        os.system("taosdump -i /tmp")
+
+        tdSql.query("show databases")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'db')
+        
+        tdSql.execute("use db")
+        tdSql.query("show stables")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'st')
+
+        tdSql.query("show tables")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 0, 't2')
+        tdSql.checkData(1, 0, 't1')
+
+        tdSql.query("select * from t1")
+        tdSql.checkRows(100)
+        for i in range(100):
+            tdSql.checkData(i, 1, i)
+            tdSql.checkData(i, 2, "nchar%d" % i)
+
+        tdSql.query("select * from t2")
+        tdSql.checkRows(100)
+        for i in range(100):
+            tdSql.checkData(i, 1, i)
+            tdSql.checkData(i, 2, "nchar%d" % i)
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file

From 431fc93950be86183926fa2503529810d93ec7fd Mon Sep 17 00:00:00 2001
From: Ping Xiao <pxiao@taosdata.com>
Date: Wed, 25 Nov 2020 16:15:22 +0800
Subject: [PATCH 28/41] add test cases into fulltest.sh

---
 tests/pytest/fulltest.sh                            | 4 +++-
 tests/pytest/tools/{lowa.py => lowaTest.py}         | 0
 tests/pytest/tools/{taosdemo.py => taosdemoTest.py} | 0
 3 files changed, 3 insertions(+), 1 deletion(-)
 rename tests/pytest/tools/{lowa.py => lowaTest.py} (100%)
 rename tests/pytest/tools/{taosdemo.py => taosdemoTest.py} (100%)

diff --git a/tests/pytest/fulltest.sh b/tests/pytest/fulltest.sh
index 525fbad6c1..89b5b0f125 100755
--- a/tests/pytest/fulltest.sh
+++ b/tests/pytest/fulltest.sh
@@ -205,7 +205,9 @@ python3 test.py -f query/queryInterval.py
 python3 test.py -f query/queryFillTest.py
 
 # tools
-python3 test.py -f tools/taosdemo.py
+python3 test.py -f tools/taosdemoTest.py
+python3 test.py -f tools/taosdumpTest.py
+python3 test.py -f tools/lowaTest.py
 
 # subscribe
 python3 test.py -f subscribe/singlemeter.py
diff --git a/tests/pytest/tools/lowa.py b/tests/pytest/tools/lowaTest.py
similarity index 100%
rename from tests/pytest/tools/lowa.py
rename to tests/pytest/tools/lowaTest.py
diff --git a/tests/pytest/tools/taosdemo.py b/tests/pytest/tools/taosdemoTest.py
similarity index 100%
rename from tests/pytest/tools/taosdemo.py
rename to tests/pytest/tools/taosdemoTest.py

From aeed9db84c8b752eabc0577477f78733e33519a8 Mon Sep 17 00:00:00 2001
From: Hui Li <huili@taosdata.com>
Date: Thu, 26 Nov 2020 09:27:17 +0800
Subject: [PATCH 29/41] [TD-2230]<fix> use error max len when dump in

---
 src/kit/taosdump/taosdump.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/kit/taosdump/taosdump.c b/src/kit/taosdump/taosdump.c
index 88f07ee602..a7258c9724 100644
--- a/src/kit/taosdump/taosdump.c
+++ b/src/kit/taosdump/taosdump.c
@@ -2146,7 +2146,7 @@ int taosDumpInOneFile(TAOS     * taos, FILE* fp, char* fcharset, char* encode, c
   char *    line     = NULL;
   size_t    line_len = 0;
 
-  cmd  = (char *)malloc(COMMAND_SIZE);
+  cmd  = (char *)malloc(TSDB_MAX_ALLOWED_SQL_LEN);
   if (cmd == NULL) {
     fprintf(stderr, "failed to allocate memory\n");
     return -1;
@@ -2155,7 +2155,7 @@ int taosDumpInOneFile(TAOS     * taos, FILE* fp, char* fcharset, char* encode, c
   int lineNo = 0;
   while ((read_len = getline(&line, &line_len, fp)) != -1) {
     ++lineNo;
-    if (read_len >= COMMAND_SIZE) continue;
+    if (read_len >= TSDB_MAX_ALLOWED_SQL_LEN) continue;
     line[--read_len] = '\0';
 
     //if (read_len == 0 || isCommentLine(line)) {  // line starts with #
@@ -2176,7 +2176,7 @@ int taosDumpInOneFile(TAOS     * taos, FILE* fp, char* fcharset, char* encode, c
       fprintf(stderr, "error sql: linenu:%d, file:%s\n", lineNo, fileName);
     }
 
-    memset(cmd, 0, COMMAND_SIZE);
+    memset(cmd, 0, TSDB_MAX_ALLOWED_SQL_LEN);
     cmd_len = 0;
   }
 

From 4f2d7a1a83c00d900fda99ee174e8008f89bfc02 Mon Sep 17 00:00:00 2001
From: Bomin Zhang <bmzhang@taosdata.com>
Date: Thu, 26 Nov 2020 04:07:38 +0000
Subject: [PATCH 30/41] [TD-2216]<fix>: crash in qUtil.c

---
 src/query/inc/qUtil.h |  2 +-
 src/query/src/qUtil.c | 12 +++++++++---
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/query/inc/qUtil.h b/src/query/inc/qUtil.h
index bc23ffadd4..8b84ac0182 100644
--- a/src/query/inc/qUtil.h
+++ b/src/query/inc/qUtil.h
@@ -27,7 +27,7 @@
 int32_t getOutputInterResultBufSize(SQuery* pQuery);
 
 void clearResultRow(SQueryRuntimeEnv* pRuntimeEnv, SResultRow* pRow, int16_t type);
-void copyResultRow(SQueryRuntimeEnv* pRuntimeEnv, SResultRow* dst, const SResultRow* src);
+void copyResultRow(SQueryRuntimeEnv* pRuntimeEnv, SResultRow* dst, const SResultRow* src, int16_t type);
 SResultRowCellInfo* getResultCell(SQueryRuntimeEnv* pRuntimeEnv, const SResultRow* pRow, int32_t index);
 
 int32_t initWindowResInfo(SWindowResInfo* pWindowResInfo, int32_t size, int32_t threshold, int16_t type);
diff --git a/src/query/src/qUtil.c b/src/query/src/qUtil.c
index 2b4cdef9b0..3f56366db8 100644
--- a/src/query/src/qUtil.c
+++ b/src/query/src/qUtil.c
@@ -133,7 +133,7 @@ void clearFirstNWindowRes(SQueryRuntimeEnv *pRuntimeEnv, int32_t num) {
   
   // clear all the closed windows from the window list
   for (int32_t k = 0; k < remain; ++k) {
-    copyResultRow(pRuntimeEnv, pWindowResInfo->pResult[k], pWindowResInfo->pResult[num + k]);
+    copyResultRow(pRuntimeEnv, pWindowResInfo->pResult[k], pWindowResInfo->pResult[num + k], type);
   }
   
   // move the unclosed window in the front of the window list
@@ -272,9 +272,15 @@ void clearResultRow(SQueryRuntimeEnv *pRuntimeEnv, SResultRow *pWindowRes, int16
  * since the attribute of "Pos" is bound to each window result when the window result is created in the
  * disk-based result buffer.
  */
-void copyResultRow(SQueryRuntimeEnv *pRuntimeEnv, SResultRow *dst, const SResultRow *src) {
+void copyResultRow(SQueryRuntimeEnv *pRuntimeEnv, SResultRow *dst, const SResultRow *src, int16_t type) {
   dst->numOfRows = src->numOfRows;
-  dst->win   = src->win;
+
+  if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
+    dst->key = realloc(dst->key, varDataTLen(src->key));
+    varDataCopy(dst->key, src->key);
+  } else {
+    dst->win   = src->win;
+  }
   dst->closed = src->closed;
   
   int32_t nOutputCols = pRuntimeEnv->pQuery->numOfOutput;

From e9c83f8251545936fe424a9004ddb4c6003c8612 Mon Sep 17 00:00:00 2001
From: zyyang <zyyang@taosdata.com>
Date: Thu, 26 Nov 2020 14:33:53 +0800
Subject: [PATCH 31/41] [TD-2132]<test>: add memory leak test case

---
 .../jdbc/cases/AppMemoryLeakTest.java         | 41 ++++++++++++++-----
 1 file changed, 31 insertions(+), 10 deletions(-)

diff --git a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/AppMemoryLeakTest.java b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/AppMemoryLeakTest.java
index 8a3dbb2bc1..8de2e3b442 100644
--- a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/AppMemoryLeakTest.java
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/AppMemoryLeakTest.java
@@ -5,19 +5,40 @@ import org.junit.Test;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;
+import java.sql.Statement;
 
 public class AppMemoryLeakTest {
 
-    @Test
-    public void testAppMemoryLeak() {
-        try {
-            Class.forName("com.taosdata.jdbc.TSDBDriver");
-
-            while (true) {
-                DriverManager.getConnection("jdbc:TAOS://localhost:6030/?user=root&password=taosdata");
-            }
-        } catch (ClassNotFoundException | SQLException e) {
-            e.printStackTrace();
+    @Test(expected = SQLException.class)
+    public void testCreateTooManyConnection() throws ClassNotFoundException, SQLException {
+        Class.forName("com.taosdata.jdbc.TSDBDriver");
+        int conCnt = 0;
+        while (true) {
+            Connection conn = DriverManager.getConnection("jdbc:TAOS://localhost:6030/?user=root&password=taosdata");
+            System.out.println(conCnt++ + " : " + conn);
         }
     }
+
+    @Test
+    public void testCreateTooManyStatement() throws ClassNotFoundException, SQLException {
+        Class.forName("com.taosdata.jdbc.TSDBDriver");
+        int stmtCnt = 0;
+        Connection conn = DriverManager.getConnection("jdbc:TAOS://localhost:6030/?user=root&password=taosdata");
+        while (true) {
+            Statement stmt = conn.createStatement();
+            System.out.println(++stmtCnt + " : " + stmt);
+        }
+    }
+
+    public static void main(String[] args) throws ClassNotFoundException, SQLException {
+        Class.forName("com.taosdata.jdbc.TSDBDriver");
+        int stmtCnt = 0;
+        Connection conn = DriverManager.getConnection("jdbc:TAOS://localhost:6030/?user=root&password=taosdata");
+        while (true) {
+            Statement stmt = conn.createStatement();
+            System.out.println(++stmtCnt + " : " + stmt);
+        }
+    }
+
+
 }

From d3729d273b5b1f200df77b2f1fc137148b2e5ff9 Mon Sep 17 00:00:00 2001
From: liuyq-617 <yqliu@taosdata.com>
Date: Thu, 26 Nov 2020 15:09:41 +0800
Subject: [PATCH 32/41] <test>add test for column which not exist

---
 tests/pytest/concurrent_inquiry.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/pytest/concurrent_inquiry.py b/tests/pytest/concurrent_inquiry.py
index 5d1e9a7537..6f4258312d 100644
--- a/tests/pytest/concurrent_inquiry.py
+++ b/tests/pytest/concurrent_inquiry.py
@@ -146,7 +146,7 @@ class ConcurrentInquiry:
             col_list=self.stb_stru_list[tbi-1]
             tag_list=self.stb_tag_list[tbi-1]
             is_stb=1
-        tlist=col_list+tag_list
+        tlist=col_list+tag_list+['abc']            #增加不存在的域'abc'，是否会引起新bug
         con_rand=random.randint(0,len(condition_list))
         func_rand=random.randint(0,len(func_list))
         col_rand=random.randint(0,len(col_list))

From f547e29a55e57031d035c77bc685e813ffaad772 Mon Sep 17 00:00:00 2001
From: Bomin Zhang <bmzhang@taosdata.com>
Date: Thu, 26 Nov 2020 07:39:47 +0000
Subject: [PATCH 33/41] [TD-2135]<patch>: reduce memory usage

---
 src/client/inc/tsclient.h       |  2 +-
 src/client/src/tscParseInsert.c | 20 ++++++++++++++------
 src/client/src/tscServer.c      | 28 +++++++++++++++++++---------
 src/client/src/tscUtil.c        | 16 ++++++++++++++--
 4 files changed, 48 insertions(+), 18 deletions(-)

diff --git a/src/client/inc/tsclient.h b/src/client/inc/tsclient.h
index ff36cf0f5a..c482375bff 100644
--- a/src/client/inc/tsclient.h
+++ b/src/client/inc/tsclient.h
@@ -282,7 +282,7 @@ typedef struct {
 
   int8_t       dataSourceType;     // load data from file or not
   int8_t       submitSchema; // submit block is built with table schema
-  STagData     tagData;
+  STagData    *pTagData;     // NOTE: pTagData->data is used as a variant length array
   SHashObj    *pTableList;   // referred table involved in sql
   SArray      *pDataBlocks;  // SArray<STableDataBlocks*> submit data blocks after parsing sql
 } SSqlCmd;
diff --git a/src/client/src/tscParseInsert.c b/src/client/src/tscParseInsert.c
index a44a158f93..6de8195d73 100644
--- a/src/client/src/tscParseInsert.c
+++ b/src/client/src/tscParseInsert.c
@@ -790,9 +790,6 @@ static int32_t tscCheckIfCreateTable(char **sqlstr, SSqlObj *pSql) {
     sql += index;
 
     tscAllocPayload(pCmd, sizeof(STagData));
-    STagData *pTag = &pCmd->tagData;
-
-    memset(pTag, 0, sizeof(STagData));
     
     //the source super table is moved to the secondary position of the pTableMetaInfo list
     if (pQueryInfo->numOfTables < 2) {
@@ -805,7 +802,14 @@ static int32_t tscCheckIfCreateTable(char **sqlstr, SSqlObj *pSql) {
       return code;
     }
 
+    STagData *pTag = realloc(pCmd->pTagData, offsetof(STagData, data));
+    if (pTag == NULL) {
+      return TSDB_CODE_TSC_OUT_OF_MEMORY;
+    }
+    memset(pTag, 0, offsetof(STagData, data));
     tstrncpy(pTag->name, pSTableMeterMetaInfo->name, sizeof(pTag->name));
+    pCmd->pTagData = pTag;
+
     code = tscGetTableMeta(pSql, pSTableMeterMetaInfo);
     if (code != TSDB_CODE_SUCCESS) {
       return code;
@@ -934,7 +938,13 @@ static int32_t tscCheckIfCreateTable(char **sqlstr, SSqlObj *pSql) {
       return TSDB_CODE_TSC_OUT_OF_MEMORY;
     }
     tdSortKVRowByColIdx(row);
-    pTag->dataLen = kvRowLen(row);
+
+    pTag = (STagData*)realloc(pCmd->pTagData, offsetof(STagData, data) + kvRowLen(row));
+    if (pTag == NULL) {
+      return TSDB_CODE_TSC_OUT_OF_MEMORY;
+    }
+    pCmd->pTagData = pTag;
+    pTag->dataLen = htonl(kvRowLen(row));
     kvRowCpy(pTag->data, row);
     free(row);
 
@@ -945,8 +955,6 @@ static int32_t tscCheckIfCreateTable(char **sqlstr, SSqlObj *pSql) {
       return tscSQLSyntaxErrMsg(pCmd->payload, ") expected", sToken.z);
     }
 
-    pTag->dataLen = htonl(pTag->dataLen);
-
     if (tscValidateName(&tableToken) != TSDB_CODE_SUCCESS) {
       return tscInvalidSQLErrMsg(pCmd->payload, "invalid table name", *sqlstr);
     }
diff --git a/src/client/src/tscServer.c b/src/client/src/tscServer.c
index 15859674ab..9735e26ece 100644
--- a/src/client/src/tscServer.c
+++ b/src/client/src/tscServer.c
@@ -1565,11 +1565,11 @@ int tscBuildTableMetaMsg(SSqlObj *pSql, SSqlInfo *pInfo) {
 
   char *pMsg = (char *)pInfoMsg + sizeof(STableInfoMsg);
 
-  size_t len = htonl(pCmd->tagData.dataLen);
-  if (pSql->cmd.autoCreated) {
+  if (pCmd->autoCreated && pCmd->pTagData != NULL) {
+    int len = htonl(pCmd->pTagData->dataLen);
     if (len > 0) {
-      len += sizeof(pCmd->tagData.name) + sizeof(pCmd->tagData.dataLen);
-      memcpy(pInfoMsg->tags, &pCmd->tagData, len);
+      len += sizeof(pCmd->pTagData->name) + sizeof(pCmd->pTagData->dataLen);
+      memcpy(pInfoMsg->tags, pCmd->pTagData, len);
       pMsg += len;
     }
   }
@@ -2239,8 +2239,6 @@ static int32_t getTableMetaFromMgmt(SSqlObj *pSql, STableMetaInfo *pTableMetaInf
   pNew->signature = pNew;
   pNew->cmd.command = TSDB_SQL_META;
 
-  registerSqlObj(pNew);
-
   tscAddSubqueryInfo(&pNew->cmd);
 
   SQueryInfo *pNewQueryInfo = tscGetQueryInfoDetailSafely(&pNew->cmd, 0);
@@ -2248,8 +2246,7 @@ static int32_t getTableMetaFromMgmt(SSqlObj *pSql, STableMetaInfo *pTableMetaInf
   pNew->cmd.autoCreated = pSql->cmd.autoCreated;  // create table if not exists
   if (TSDB_CODE_SUCCESS != tscAllocPayload(&pNew->cmd, TSDB_DEFAULT_PAYLOAD_SIZE + pSql->cmd.payloadLen)) {
     tscError("%p malloc failed for payload to get table meta", pSql);
-    free(pNew);
-
+    tscFreeSqlObj(pNew);
     return TSDB_CODE_TSC_OUT_OF_MEMORY;
   }
 
@@ -2257,12 +2254,25 @@ static int32_t getTableMetaFromMgmt(SSqlObj *pSql, STableMetaInfo *pTableMetaInf
   assert(pNew->cmd.numOfClause == 1 && pNewQueryInfo->numOfTables == 1);
 
   tstrncpy(pNewMeterMetaInfo->name, pTableMetaInfo->name, sizeof(pNewMeterMetaInfo->name));
-  memcpy(&pNew->cmd.tagData, &pSql->cmd.tagData, sizeof(pSql->cmd.tagData));
+
+  if (pSql->cmd.pTagData != NULL) {
+    int size = offsetof(STagData, data) + htonl(pSql->cmd.pTagData->dataLen);
+    pNew->cmd.pTagData = calloc(1, size);
+    if (pNew->cmd.pTagData == NULL) {
+      tscError("%p malloc failed for new tag data to get table meta", pSql);
+      tscFreeSqlObj(pNew);
+      return TSDB_CODE_TSC_OUT_OF_MEMORY;
+    }
+    memcpy(pNew->cmd.pTagData, pSql->cmd.pTagData, size);
+  }
+
   tscDebug("%p new pSqlObj:%p to get tableMeta, auto create:%d", pSql, pNew, pNew->cmd.autoCreated);
 
   pNew->fp = tscTableMetaCallBack;
   pNew->param = pSql;
 
+  registerSqlObj(pNew);
+
   int32_t code = tscProcessSql(pNew);
   if (code == TSDB_CODE_SUCCESS) {
     code = TSDB_CODE_TSC_ACTION_IN_PROGRESS;  // notify upper application that current process need to be terminated
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index a75f6d8296..d22c2588cc 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -408,7 +408,7 @@ void tscResetSqlCmdObj(SSqlCmd* pCmd, bool removeFromCache) {
   pCmd->pTableList = NULL;
   
   pCmd->pDataBlocks = tscDestroyBlockArrayList(pCmd->pDataBlocks);
-  
+
   tscFreeQueryInfo(pCmd, removeFromCache);
 }
 
@@ -512,6 +512,8 @@ void tscFreeSqlObj(SSqlObj* pSql) {
   tscFreeSqlResult(pSql);
   tscResetSqlCmdObj(pCmd, false);
 
+  tfree(pCmd->pTagData);
+  
   memset(pCmd->payload, 0, (size_t)pCmd->allocSize);
   tfree(pCmd->payload);
   pCmd->allocSize = 0;
@@ -1909,7 +1911,17 @@ SSqlObj* createSimpleSubObj(SSqlObj* pSql, void (*fp)(), void* param, int32_t cm
   pCmd->command = cmd;
   pCmd->parseFinished = 1;
   pCmd->autoCreated = pSql->cmd.autoCreated;
-  memcpy(&pCmd->tagData, &pSql->cmd.tagData, sizeof(pCmd->tagData));
+
+  if (pSql->cmd.pTagData != NULL) {
+    int size = offsetof(STagData, data) + htonl(pSql->cmd.pTagData->dataLen);
+    pNew->cmd.pTagData = calloc(1, size);
+    if (pNew->cmd.pTagData == NULL) {
+      tscError("%p new subquery failed, unable to malloc tag data, tableIndex:%d", pSql, 0);
+      free(pNew);
+      return NULL;
+    }
+    memcpy(pNew->cmd.pTagData, pSql->cmd.pTagData, size);
+  }
 
   if (tscAddSubqueryInfo(pCmd) != TSDB_CODE_SUCCESS) {
     tscFreeSqlObj(pNew);

From 55ce69e2f0c08aed576b46bf11cff1a7b7bc2d4a Mon Sep 17 00:00:00 2001
From: Bomin Zhang <bmzhang@taosdata.com>
Date: Thu, 26 Nov 2020 08:00:58 +0000
Subject: [PATCH 34/41] [TD-2182]<fix>: coverity issues

---
 src/client/src/tscSub.c   | 7 ++++++-
 src/query/src/qExecutor.c | 6 +++---
 src/util/src/tqueue.c     | 3 ---
 3 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/client/src/tscSub.c b/src/client/src/tscSub.c
index 2c81bd7c7c..a782b53e75 100644
--- a/src/client/src/tscSub.c
+++ b/src/client/src/tscSub.c
@@ -442,7 +442,12 @@ TAOS_RES *taos_consume(TAOS_SUB *tsub) {
 
   size_t size = taosArrayGetSize(pSub->progress) * sizeof(STableIdInfo);
   size += sizeof(SQueryTableMsg) + 4096;
-  tscAllocPayload(&pSql->cmd, (int)size);
+  int code = tscAllocPayload(&pSql->cmd, (int)size);
+  if (code != TSDB_CODE_SUCCESS) {
+    tscError("failed to alloc payload");
+    return NULL;
+  }
+
   for (int retry = 0; retry < 3; retry++) {
     tscRemoveFromSqlList(pSql);
 
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index fce25ae119..826858d1dd 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -5836,9 +5836,9 @@ static int32_t convertQueryMsg(SQueryTableMsg *pQueryMsg, SArray **pTableIdList,
   pQueryMsg->interval.interval = htobe64(pQueryMsg->interval.interval);
   pQueryMsg->interval.sliding = htobe64(pQueryMsg->interval.sliding);
   pQueryMsg->interval.offset = htobe64(pQueryMsg->interval.offset);
-  pQueryMsg->interval.intervalUnit = pQueryMsg->interval.intervalUnit;
-  pQueryMsg->interval.slidingUnit = pQueryMsg->interval.slidingUnit;
-  pQueryMsg->interval.offsetUnit = pQueryMsg->interval.offsetUnit;
+  // pQueryMsg->interval.intervalUnit = pQueryMsg->interval.intervalUnit;
+  // pQueryMsg->interval.slidingUnit = pQueryMsg->interval.slidingUnit;
+  // pQueryMsg->interval.offsetUnit = pQueryMsg->interval.offsetUnit;
   pQueryMsg->limit = htobe64(pQueryMsg->limit);
   pQueryMsg->offset = htobe64(pQueryMsg->offset);
 
diff --git a/src/util/src/tqueue.c b/src/util/src/tqueue.c
index d3c17e7626..143ce7c474 100644
--- a/src/util/src/tqueue.c
+++ b/src/util/src/tqueue.c
@@ -79,15 +79,12 @@ void taosCloseQueue(taos_queue param) {
 
   if (queue->qset) taosRemoveFromQset(qset, queue); 
 
-  pthread_mutex_lock(&queue->mutex);
-
   while (pNode) {
     pTemp = pNode;
     pNode = pNode->next;
     free (pTemp);
   }
 
-  pthread_mutex_unlock(&queue->mutex);
   pthread_mutex_destroy(&queue->mutex);
   free(queue);
 

From 651672957d470f715b265c29892f495d62c94da0 Mon Sep 17 00:00:00 2001
From: Ping Xiao <pxiao@taosdata.com>
Date: Thu, 26 Nov 2020 16:32:10 +0800
Subject: [PATCH 35/41] [TD-2240] <test> update restfulInsert

---
 tests/pytest/insert/restfulInsert.py | 37 ++++++++++++++++++----------
 1 file changed, 24 insertions(+), 13 deletions(-)

diff --git a/tests/pytest/insert/restfulInsert.py b/tests/pytest/insert/restfulInsert.py
index c39d1cbe48..e3a963f1d4 100644
--- a/tests/pytest/insert/restfulInsert.py
+++ b/tests/pytest/insert/restfulInsert.py
@@ -18,10 +18,10 @@ import time
 import argparse
 
 class RestfulInsert:
-    def __init__(self, host, dbname, threads, tables, records, batchSize, tbNamePerfix, outOfOrder):
+    def __init__(self, host, startTimestamp, dbname, threads, tables, records, batchSize, tbNamePerfix, outOfOrder):
         self.header = {'Authorization': 'Basic cm9vdDp0YW9zZGF0YQ=='}
         self.url = "http://%s:6041/rest/sql" % host
-        self.ts = 1500000000000
+        self.ts = startTimestamp
         self.dbname = dbname
         self.numOfThreads = threads
         self.numOfTables = tables
@@ -36,8 +36,10 @@ class RestfulInsert:
         for i in range(tablesPerThread):
             tableID = threadID * tablesPerThread
             name = 'beijing' if tableID % 2 == 0 else 'shanghai'
-            data = "create table %s.%s%d using %s.meters tags(%d, '%s')" % (self.dbname, self.tableNamePerfix, tableID + i, self.dbname, tableID + i, name)
-            requests.post(self.url, data, headers = self.header)
+            data = "create table if not exists %s.%s%d using %s.meters tags(%d, '%s')" % (self.dbname, self.tableNamePerfix, tableID + i, self.dbname, tableID + i, name)
+            response = requests.post(self.url, data, headers = self.header)
+            if response.status_code != 200:
+                    print(response.content)
 
     def insertData(self, threadID):        
         print("thread %d started" % threadID)
@@ -50,7 +52,9 @@ class RestfulInsert:
                 values = []
                 for k in range(self.batchSize):
                     data +=  "(%d, %d, %d, %d)" %  (start + j * self.batchSize + k, random.randint(1, 100), random.randint(1, 100), random.randint(1, 100))                                
-                requests.post(self.url, data, headers = self.header)
+                response = requests.post(self.url, data, headers = self.header)
+                if response.status_code != 200:
+                    print(response.content)
 
     def insertUnlimitedData(self, threadID):        
         print("thread %d started" % threadID)
@@ -76,15 +80,15 @@ class RestfulInsert:
                 else:
                     random.shuffle(values)
                     for k in range(len(values)):            
-                        data += values[k]
-                requests.post(self.url, data, headers = self.header)
+                        data += values[k]                
+                response = requests.post(self.url, data, headers = self.header)
+                if response.status_code != 200:
+                    print(response.content)
 
-    def run(self):
-        data = "drop database if exists %s" % self.dbname
+    def run(self):                
+        data = "create database if not exists %s" % self.dbname
         requests.post(self.url, data, headers = self.header)
-        data = "create database %s" % self.dbname
-        requests.post(self.url, data, headers = self.header)
-        data = "create table %s.meters(ts timestamp, f1 int, f2 int, f3 int) tags(id int, loc nchar(20))" % self.dbname
+        data = "create table if not exists %s.meters(ts timestamp, f1 int, f2 int, f3 int) tags(id int, loc nchar(20))" % self.dbname
         requests.post(self.url, data, headers = self.header)
 
         threads = []
@@ -120,6 +124,13 @@ parser.add_argument(
     default='127.0.0.1',
     type=str,
     help='host name to be connected (default: 127.0.0.1)')
+parser.add_argument(
+    '-S',
+    '--start-timestamp',
+    action='store',
+    default=1500000000000,
+    type=int,
+    help='insert data from timestamp (default: 1500000000000)')
 parser.add_argument(
     '-d',
     '--db-name',
@@ -169,5 +180,5 @@ parser.add_argument(
     help='The order of test data (default: False)')
 
 args = parser.parse_args()
-ri = RestfulInsert(args.host_name, args.db_name, args.number_of_threads, args.number_of_tables, args.number_of_records, args.batch_size, args.table_name_prefix, args.out_of_order)
+ri = RestfulInsert(args.host_name, args.start_timestamp, args.db_name, args.number_of_threads, args.number_of_tables, args.number_of_records, args.batch_size, args.table_name_prefix, args.out_of_order)
 ri.run()
\ No newline at end of file

From fa25d38dea8ec9e310c85fac1da6aa36c70104ef Mon Sep 17 00:00:00 2001
From: liuyq-617 <yqliu@taosdata.com>
Date: Thu, 26 Nov 2020 16:37:11 +0800
Subject: [PATCH 36/41] <test>full test

---
 tests/test-all.sh | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/tests/test-all.sh b/tests/test-all.sh
index ff47cbfd71..5897978bce 100755
--- a/tests/test-all.sh
+++ b/tests/test-all.sh
@@ -17,9 +17,9 @@ function runSimCaseOneByOne {
         echo -e "${GREEN}$case success${NC}" | tee -a out.log || \
         echo -e "${RED}$case failed${NC}" | tee -a out.log
       out_log=`tail -1 out.log  `
-      if [[ $out_log =~ 'failed' ]];then
-        exit 8
-      fi
+      # if [[ $out_log =~ 'failed' ]];then
+      #   exit 8
+      # fi
       end_time=`date +%s`
       echo execution time of $case was `expr $end_time - $start_time`s. | tee -a out.log
     fi
@@ -42,9 +42,9 @@ function runPyCaseOneByOne {
           echo -e "${RED}$case failed${NC}" | tee -a pytest-out.log
         end_time=`date +%s`
         out_log=`tail -1 pytest-out.log  `
-        if [[ $out_log =~ 'failed' ]];then
-          exit 8
-        fi
+        # if [[ $out_log =~ 'failed' ]];then
+        #   exit 8
+        # fi
         echo execution time of $case was `expr $end_time - $start_time`s. | tee -a pytest-out.log
       else
         $line > /dev/null 2>&1

From 19eccc86ade72ded17cd4c4033b44b275137dc0f Mon Sep 17 00:00:00 2001
From: Hongze Cheng <hzcheng@taosdata.com>
Date: Thu, 26 Nov 2020 08:44:20 +0000
Subject: [PATCH 37/41] fix TD-2184

---
 src/tsdb/src/tsdbMemTable.c | 4 ++--
 src/util/src/tskiplist.c    | 5 ++++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/tsdb/src/tsdbMemTable.c b/src/tsdb/src/tsdbMemTable.c
index 71944c87c6..4c51608b5d 100644
--- a/src/tsdb/src/tsdbMemTable.c
+++ b/src/tsdb/src/tsdbMemTable.c
@@ -871,10 +871,10 @@ static void tsdbFreeRows(STsdbRepo *pRepo, void **rows, int rowCounter) {
                 listNEles(pRepo->mem->bufBlockList), pBufBlock->offset, pBufBlock->remain);
 
       if (pBufBlock->offset == 0) {  // return the block to buffer pool
-        tsdbLockRepo(pRepo);
+        if (tsdbLockRepo(pRepo) < 0) return;
         SListNode *pNode = tdListPopTail(pRepo->mem->bufBlockList);
         tdListPrependNode(pBufPool->bufBlockList, pNode);
-        tsdbUnlockRepo(pRepo);
+        if (tsdbUnlockRepo(pRepo) < 0) return;
       }
     } else {
       ASSERT(listNEles(pRepo->mem->extraBuffList) > 0);
diff --git a/src/util/src/tskiplist.c b/src/util/src/tskiplist.c
index a36f7f0261..20bec16954 100644
--- a/src/util/src/tskiplist.c
+++ b/src/util/src/tskiplist.c
@@ -291,7 +291,10 @@ bool tSkipListIterNext(SSkipListIterator *iter) {
     iter->next = SL_NODE_GET_FORWARD_POINTER(iter->cur, 0);
     iter->step++;
   } else {
-    if (iter->cur == pSkipList->pHead) return false;
+    if (iter->cur == pSkipList->pHead) {
+      tSkipListUnlock(pSkipList);
+      return false;
+    }
     iter->cur = SL_NODE_GET_BACKWARD_POINTER(iter->cur, 0);
 
     // a new node is inserted into between iter->cur and iter->next, ignore it

From 86479c1f6a42a97d0ef5d880e18565eae1660ded Mon Sep 17 00:00:00 2001
From: Shengliang Guan <slguan@taosdata.com>
Date: Fri, 27 Nov 2020 11:33:44 +0800
Subject: [PATCH 38/41] TD-2246

---
 tests/test/c/CMakeLists.txt |  7 ++--
 tests/test/c/hashIterator.c | 72 +++++++++++++++++++++++++++++++++++++
 2 files changed, 77 insertions(+), 2 deletions(-)
 create mode 100644 tests/test/c/hashIterator.c

diff --git a/tests/test/c/CMakeLists.txt b/tests/test/c/CMakeLists.txt
index 26aa20e647..11480a8ba2 100644
--- a/tests/test/c/CMakeLists.txt
+++ b/tests/test/c/CMakeLists.txt
@@ -31,8 +31,8 @@ IF (TD_LINUX)
   #add_executable(createTablePerformance createTablePerformance.c)
   #target_link_libraries(createTablePerformance taos_static tutil common pthread)
 
-  #add_executable(createNormalTable createNormalTable.c)
-  #target_link_libraries(createNormalTable taos_static tutil common pthread)
+  add_executable(createNormalTable createNormalTable.c)
+  target_link_libraries(createNormalTable taos_static tutil common pthread)
 
   #add_executable(queryPerformance queryPerformance.c)
   #target_link_libraries(queryPerformance taos_static tutil common pthread)
@@ -45,5 +45,8 @@ IF (TD_LINUX)
 
   #add_executable(invalidTableId invalidTableId.c)
   #target_link_libraries(invalidTableId taos_static tutil common pthread)
+
+  add_executable(hashIterator hashIterator.c)
+  target_link_libraries(hashIterator taos_static tutil common pthread)
 ENDIF()
 
diff --git a/tests/test/c/hashIterator.c b/tests/test/c/hashIterator.c
new file mode 100644
index 0000000000..cbd8a0895e
--- /dev/null
+++ b/tests/test/c/hashIterator.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define _DEFAULT_SOURCE
+#include "os.h"
+#include "taos.h"
+#include "tulog.h"
+#include "tutil.h"
+#include "hash.h"
+
+typedef struct HashTestRow {
+  int32_t keySize;
+  char    key[100];
+} HashTestRow;
+
+int main(int argc, char *argv[]) {
+  _hash_fn_t hashFp = taosGetDefaultHashFunction(TSDB_DATA_TYPE_BINARY);
+  void *     hashHandle = taosHashInit(100, hashFp, true, HASH_ENTRY_LOCK);
+
+  pPrint("insert 3 rows to hash");
+  for (int32_t t = 0; t < 3; ++t) {
+    HashTestRow row = {0};
+    row.keySize = sprintf(row.key, "0.db.st%d", t);
+
+    taosHashPut(hashHandle, row.key, row.keySize, &row, sizeof(HashTestRow));
+  }
+
+  pPrint("start iterator");
+  HashTestRow *row = taosHashIterate(hashHandle, NULL);
+  while (row) {
+    pPrint("drop key:%s", row->key);
+    taosHashRemove(hashHandle, row->key, row->keySize);
+
+    pPrint("get rows from hash");
+    for (int32_t t = 0; t < 3; ++t) {
+      HashTestRow r = {0};
+      r.keySize = sprintf(r.key, "0.db.st%d", t);
+
+      void *result = taosHashGet(hashHandle, r.key, r.keySize);
+      pPrint("get key:%s result:%p", r.key, result);
+    }
+
+    //Before getting the next iterator, the object just deleted can be obtained
+    row = taosHashIterate(hashHandle, row);
+  }
+
+  pPrint("stop iterator");
+  taosHashCancelIterate(hashHandle, row);
+
+  pPrint("get rows from hash");
+  for (int32_t t = 0; t < 3; ++t) {
+    HashTestRow r = {0};
+    r.keySize = sprintf(r.key, "0.db.st%d", t);
+
+    void *result = taosHashGet(hashHandle, r.key, r.keySize);
+    pPrint("get key:%s result:%p", r.key, result);
+  }
+
+  return 0;
+}
\ No newline at end of file

From 4b09f05290596014d987bcdc8c34d2004814618e Mon Sep 17 00:00:00 2001
From: Jeff Tao <jhtao@taosdata.com>
Date: Fri, 27 Nov 2020 07:23:16 +0000
Subject: [PATCH 39/41] add a removed flag in pNode

---
 src/connector/go            |  2 +-
 src/connector/grafanaplugin |  2 +-
 src/rpc/src/rpcTcp.c        | 15 +++++++++------
 src/util/inc/hash.h         |  1 +
 src/util/src/hash.c         | 19 +++++++++++++++----
 5 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/src/connector/go b/src/connector/go
index 050667e5b4..8c58c512b6 160000
--- a/src/connector/go
+++ b/src/connector/go
@@ -1 +1 @@
-Subproject commit 050667e5b4d0eafa5387e4283e713559b421203f
+Subproject commit 8c58c512b6acda8bcdfa48fdc7140227b5221766
diff --git a/src/connector/grafanaplugin b/src/connector/grafanaplugin
index ec77d9049a..d598db167e 160000
--- a/src/connector/grafanaplugin
+++ b/src/connector/grafanaplugin
@@ -1 +1 @@
-Subproject commit ec77d9049a719dabfd1a7c1122a209e201861944
+Subproject commit d598db167eb256fe67409b7bb3d0eb7fffc3ff8c
diff --git a/src/rpc/src/rpcTcp.c b/src/rpc/src/rpcTcp.c
index 7b8cf3cda2..2850046d05 100644
--- a/src/rpc/src/rpcTcp.c
+++ b/src/rpc/src/rpcTcp.c
@@ -371,10 +371,13 @@ void taosCloseTcpConnection(void *chandle) {
 
 int taosSendTcpData(uint32_t ip, uint16_t port, void *data, int len, void *chandle) {
   SFdObj *pFdObj = chandle;
-
   if (pFdObj == NULL || pFdObj->signature != pFdObj) return -1;
+  SThreadObj *pThreadObj = pFdObj->pThreadObj;
 
-  return taosWriteMsg(pFdObj->fd, data, len);
+  int ret = taosWriteMsg(pFdObj->fd, data, len);
+  tTrace("%s %p TCP data is sent, FD:%p fd:%d bytes:%d", pThreadObj->label, pFdObj->thandle, pFdObj, pFdObj->fd, ret); 
+
+  return ret;
 }
 
 static void taosReportBrokenLink(SFdObj *pFdObj) {
@@ -409,7 +412,7 @@ static int taosReadTcpData(SFdObj *pFdObj, SRecvInfo *pInfo) {
 
   headLen = taosReadMsg(pFdObj->fd, &rpcHead, sizeof(SRpcHead));
   if (headLen != sizeof(SRpcHead)) {
-    tDebug("%s %p read error, headLen:%d", pThreadObj->label, pFdObj->thandle, headLen);
+    tDebug("%s %p read error, FD:%p headLen:%d", pThreadObj->label, pFdObj->thandle, pFdObj, headLen);
     return -1; 
   }
 
@@ -420,7 +423,7 @@ static int taosReadTcpData(SFdObj *pFdObj, SRecvInfo *pInfo) {
     tError("%s %p TCP malloc(size:%d) fail", pThreadObj->label, pFdObj->thandle, msgLen);
     return -1;
   } else {
-    tTrace("TCP malloc mem:%p size:%d", buffer, size);
+    tTrace("%s %p read data, FD:%p fd:%d TCP malloc mem:%p", pThreadObj->label, pFdObj->thandle, pFdObj, pFdObj->fd, buffer);
   }
 
   msg = buffer + tsRpcOverhead;
@@ -583,8 +586,8 @@ static void taosFreeFdObj(SFdObj *pFdObj) {
 
   pthread_mutex_unlock(&pThreadObj->mutex);
 
-  tDebug("%s %p TCP connection is closed, FD:%p numOfFds:%d", 
-          pThreadObj->label, pFdObj->thandle, pFdObj, pThreadObj->numOfFds);
+  tDebug("%s %p TCP connection is closed, FD:%p fd:%d numOfFds:%d", 
+          pThreadObj->label, pFdObj->thandle, pFdObj, pFdObj->fd, pThreadObj->numOfFds);
 
   tfree(pFdObj);
 }
diff --git a/src/util/inc/hash.h b/src/util/inc/hash.h
index aaff48f4f8..572f1a50c6 100644
--- a/src/util/inc/hash.h
+++ b/src/util/inc/hash.h
@@ -36,6 +36,7 @@ typedef struct SHashNode {
   uint32_t          keyLen;   // length of the key
   uint32_t          dataLen;  // length of data
   int8_t            count;    // reference count
+  int8_t            removed;  // flag to indicate removed
   char              data[];
 } SHashNode;
 
diff --git a/src/util/src/hash.c b/src/util/src/hash.c
index cd9a9f7d0a..3ac54eedd8 100644
--- a/src/util/src/hash.c
+++ b/src/util/src/hash.c
@@ -76,7 +76,7 @@ static FORCE_INLINE int32_t taosHashCapacity(int32_t length) {
 static FORCE_INLINE SHashNode *doSearchInEntryList(SHashEntry *pe, const void *key, size_t keyLen, uint32_t hashVal) {
   SHashNode *pNode = pe->next;
   while (pNode) {
-    if ((pNode->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY(pNode), key, keyLen) == 0)) {
+    if ((pNode->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY(pNode), key, keyLen) == 0) && pNode->removed == 0) {
       assert(pNode->hashVal == hashVal);
       break;
     }
@@ -222,7 +222,7 @@ int32_t taosHashPut(SHashObj *pHashObj, const void *key, size_t keyLen, void *da
 
   SHashNode* prev = NULL;
   while (pNode) {
-    if ((pNode->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY(pNode), key, keyLen) == 0)) {
+    if ((pNode->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY(pNode), key, keyLen) == 0) && pNode->removed == 0) {
       assert(pNode->hashVal == hashVal);
       break;
     }
@@ -361,7 +361,7 @@ int32_t taosHashRemoveWithData(SHashObj *pHashObj, const void *key, size_t keyLe
   SHashNode *prevNode = NULL;
 
   while (pNode) {
-    if ((pNode->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY(pNode), key, keyLen) == 0)) 
+    if ((pNode->keyLen == keyLen) && (memcmp(GET_HASH_NODE_KEY(pNode), key, keyLen) == 0) && pNode->removed == 0) 
       break;
 
     prevNode = pNode;
@@ -372,6 +372,7 @@ int32_t taosHashRemoveWithData(SHashObj *pHashObj, const void *key, size_t keyLe
     code = 0;  // it is found
 
     pNode->count--;
+    pNode->removed = 1;
     if (pNode->count <= 0) {
       if (prevNode) {
         prevNode->next = pNode->next;
@@ -702,8 +703,13 @@ static void *taosHashReleaseNode(SHashObj *pHashObj, void *p, int *slot) {
     pNode = pNode->next;
   }
 
-  if (pNode) {
+  if (pNode) { 
     pNode = pNode->next;
+    while (pNode) {
+      if (pNode->removed == 0) break;
+      pNode = pNode->next;
+    }
+
     pOld->count--;
     if (pOld->count <=0) {
       if (prevNode) {
@@ -755,6 +761,11 @@ void *taosHashIterate(SHashObj *pHashObj, void *p) {
       }
 
       pNode = pe->next;
+      while (pNode) {
+        if (pNode->removed == 0) break;
+        pNode = pNode->next;
+      }
+
       if (pNode) break;
 
       if (pHashObj->type == HASH_ENTRY_LOCK) {

From 257af62edfc99dca2198eb4dc3fbb00c36d9b043 Mon Sep 17 00:00:00 2001
From: Hui Li <huili@taosdata.com>
Date: Fri, 27 Nov 2020 15:29:12 +0800
Subject: [PATCH 40/41] [TD-2258]<fix> taos_fetch_block() resutl printf error

---
 tests/examples/c/apitest.c   | 12 ++++++------
 tests/examples/c/subscribe.c |  8 ++++----
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/tests/examples/c/apitest.c b/tests/examples/c/apitest.c
index be60a88ad7..e08d667d6b 100644
--- a/tests/examples/c/apitest.c
+++ b/tests/examples/c/apitest.c
@@ -79,11 +79,11 @@ static int print_result(TAOS_RES* res, int blockFetch) {
   if (blockFetch) {
     int rows = 0;
     while ((rows = taos_fetch_block(res, &row))) {
-      for (int i = 0; i < rows; i++) {
-        char temp[256];
-        taos_print_row(temp, row + i, fields, num_fields);
-        puts(temp);
-      }
+      //for (int i = 0; i < rows; i++) {
+      //  char temp[256];
+      //  taos_print_row(temp, row + i, fields, num_fields);
+      //  puts(temp);
+      //}
       nRows += rows;
     }
   } else {
@@ -498,4 +498,4 @@ int main(int argc, char *argv[]) {
 
   taos_close(taos);
   taos_cleanup();
-}
\ No newline at end of file
+}
diff --git a/tests/examples/c/subscribe.c b/tests/examples/c/subscribe.c
index 8368af18f7..cdd8ddaf7f 100644
--- a/tests/examples/c/subscribe.c
+++ b/tests/examples/c/subscribe.c
@@ -19,10 +19,10 @@ void print_result(TAOS_RES* res, int blockFetch) {
   
   if (blockFetch) {
     nRows = taos_fetch_block(res, &row);
-    for (int i = 0; i < nRows; i++) {
-      taos_print_row(buf, row + i, fields, num_fields);
-      puts(buf);
-    }
+    //for (int i = 0; i < nRows; i++) {
+    //  taos_print_row(buf, row + i, fields, num_fields);
+    //  puts(buf);
+    //}
   } else {
     while ((row = taos_fetch_row(res))) {
       taos_print_row(buf, row, fields, num_fields);

From 15691bfb088fd114f3e53c769c2829937e746d63 Mon Sep 17 00:00:00 2001
From: Jeff Tao <jhtao@taosdata.com>
Date: Fri, 27 Nov 2020 07:41:35 +0000
Subject: [PATCH 41/41] data type compatible with windows

---
 src/util/inc/hash.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/inc/hash.h b/src/util/inc/hash.h
index 572f1a50c6..b0319d3e13 100644
--- a/src/util/inc/hash.h
+++ b/src/util/inc/hash.h
@@ -34,7 +34,7 @@ typedef struct SHashNode {
   struct SHashNode *next;
   uint32_t          hashVal;  // the hash value of key
   uint32_t          keyLen;   // length of the key
-  uint32_t          dataLen;  // length of data
+  size_t            dataLen;  // length of data
   int8_t            count;    // reference count
   int8_t            removed;  // flag to indicate removed
   char              data[];