diff --git a/cmake/version.inc b/cmake/version.inc
index 741f76da43..2f0ec81aea 100644
--- a/cmake/version.inc
+++ b/cmake/version.inc
@@ -4,7 +4,7 @@ PROJECT(TDengine)
 IF (DEFINED VERNUMBER)
   SET(TD_VER_NUMBER ${VERNUMBER})
 ELSE ()
-  SET(TD_VER_NUMBER "2.0.7.0")
+  SET(TD_VER_NUMBER "2.0.8.0")
 ENDIF ()
 
 IF (DEFINED VERCOMPATIBLE)
diff --git a/snap/snapcraft.yaml b/snap/snapcraft.yaml
index 1738ff7ec8..059c0650c2 100644
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@@ -1,6 +1,6 @@
 name: tdengine
 base: core18
-version: '2.0.7.0'
+version: '2.0.8.0'
 icon: snap/gui/t-dengine.svg
 summary: an open-source big data platform designed and optimized for IoT. 
 description: |
@@ -72,7 +72,7 @@ parts:
       - usr/bin/taosd
       - usr/bin/taos
       - usr/bin/taosdemo
-      - usr/lib/libtaos.so.2.0.6.0
+      - usr/lib/libtaos.so.2.0.8.0
       - usr/lib/libtaos.so.1
       - usr/lib/libtaos.so
 
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..743cb42eb3 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);
 
@@ -1768,10 +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);
@@ -1782,6 +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);
   }
 }
 
@@ -2056,7 +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;
@@ -2078,7 +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;
@@ -2120,7 +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;
@@ -2951,14 +2955,6 @@ 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 +3533,7 @@ 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;
       }
     }
@@ -4252,6 +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;
@@ -6531,7 +6530,7 @@ 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 cbc5604a27..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) {
@@ -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);
@@ -2030,7 +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;
   }
 
@@ -2038,6 +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/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/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/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);
+}
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/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/inc/qUtil.h b/src/query/inc/qUtil.h
index 4cd0e60ebe..bc23ffadd4 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);
 
@@ -80,5 +80,8 @@ void* destroyResultRowPool(SResultRowPool* p);
 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/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/qExecutor.c b/src/query/src/qExecutor.c
index d0874c36bc..fce25ae119 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);
 }
 
@@ -947,10 +947,10 @@ static char *getDataBlock(SQueryRuntimeEnv *pRuntimeEnv, SArithmeticSupport *sas
   if (functionId == TSDB_FUNC_ARITHM) {
     sas->pArithExpr = &pQuery->pExpr1[col];
 
-    sas->offset  = 0;
-    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);
@@ -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) {
@@ -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) {
@@ -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);
@@ -5811,6 +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);
@@ -6796,7 +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 c5ba551f20..55a7aea53a 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 = (int32_t) 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;
@@ -407,7 +410,7 @@ 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/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/src/query/src/qUtil.c b/src/query/src/qUtil.c
index c5317226c7..2b4cdef9b0 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;
 
@@ -56,6 +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);
 }
@@ -69,7 +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;
@@ -94,12 +112,8 @@ 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 +121,7 @@ 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 {
@@ -134,23 +139,16 @@ 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;
 
   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); 
 
@@ -237,7 +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;
   }
@@ -261,7 +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;
+  }
 }
 
 /**
@@ -379,3 +382,18 @@ 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;
+  }
+
+  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/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);}
diff --git a/src/sync/inc/syncInt.h b/src/sync/inc/syncInt.h
index aacd72e930..7dbb1985d4 100644
--- a/src/sync/inc/syncInt.h
+++ b/src/sync/inc/syncInt.h
@@ -172,6 +172,7 @@ typedef struct SSyncNode {
 // sync module global
 extern int32_t tsSyncNum;
 extern char    tsNodeFqdn[TSDB_FQDN_LEN];
+extern char *  syncStatus[];
 
 void *syncRetrieveData(void *param);
 void *syncRestoreData(void *param);
diff --git a/src/sync/src/syncMain.c b/src/sync/src/syncMain.c
index dd759ed9d4..8d3997a5d6 100644
--- a/src/sync/src/syncMain.c
+++ b/src/sync/src/syncMain.c
@@ -73,6 +73,14 @@ char* syncRole[] = {
   "master"
 };
 
+char *syncStatus[] = {
+  "init",
+  "start",
+  "file",
+  "cache",
+  "invalid"
+};
+
 typedef enum {
   SYNC_STATUS_BROADCAST,
   SYNC_STATUS_BROADCAST_RSP,
@@ -282,7 +290,7 @@ void syncStop(int64_t rid) {
   pPeer = pNode->peerInfo[TAOS_SYNC_MAX_REPLICA];
   if (pPeer) syncRemovePeer(pPeer);
 
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 
   taosReleaseRef(tsSyncRefId, rid);
   taosRemoveRef(tsSyncRefId, rid);
@@ -350,7 +358,7 @@ int32_t syncReconfig(int64_t rid, const SSyncCfg *pNewCfg) {
     (*pNode->notifyRole)(pNode->vgId, nodeRole);
   }
 
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 
   sInfo("vgId:%d, %d replicas are configured, quorum:%d", pNode->vgId, pNode->replica, pNode->quorum);
   syncBroadcastStatus(pNode);
@@ -423,7 +431,7 @@ void syncRecover(int64_t rid) {
     }
   }
 
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 
   taosReleaseRef(tsSyncRefId, rid);
 }
@@ -498,6 +506,8 @@ int32_t syncDecPeerRef(SSyncPeer *pPeer) {
 }
 
 static void syncClosePeerConn(SSyncPeer *pPeer) {
+  sDebug("%s, pfd:%d sfd:%d will be closed", pPeer->id, pPeer->peerFd, pPeer->syncFd);
+
   taosTmrStopA(&pPeer->timer);
   taosClose(pPeer->syncFd);
   if (pPeer->peerFd >= 0) {
@@ -751,7 +761,7 @@ static void syncCheckRole(SSyncPeer *pPeer, SPeerStatus* peersStatus, int8_t new
       sDebug("vgId:%d, choose master", pNode->vgId);
       syncChooseMaster(pNode);
     } else {
-      sDebug("vgId:%d, version inconsistent, cannot choose master", pNode->vgId);
+      sDebug("vgId:%d, cannot choose master since roles inconsistent", pNode->vgId);
     }
   }
 
@@ -770,11 +780,12 @@ static void syncCheckRole(SSyncPeer *pPeer, SPeerStatus* peersStatus, int8_t new
 }
 
 static void syncRestartPeer(SSyncPeer *pPeer) {
-  sDebug("%s, restart peer connection", pPeer->id);
+  sDebug("%s, restart peer connection, last sstatus:%s", pPeer->id, syncStatus[pPeer->sstatus]);
 
   syncClosePeerConn(pPeer);
 
   pPeer->sstatus = TAOS_SYNC_STATUS_INIT;
+  sDebug("%s, peer conn is restart and set sstatus:%s", pPeer->id, syncStatus[pPeer->sstatus]);
 
   int32_t ret = strcmp(pPeer->fqdn, tsNodeFqdn);
   if (ret > 0 || (ret == 0 && pPeer->port > tsSyncPort)) {
@@ -803,7 +814,7 @@ static void syncProcessSyncRequest(char *msg, SSyncPeer *pPeer) {
   }
 
   if (pPeer->sstatus != TAOS_SYNC_STATUS_INIT) {
-    sDebug("%s, sync is already started", pPeer->id);
+    sDebug("%s, sync is already started for sstatus:%s", pPeer->id, syncStatus[pPeer->sstatus]);
     return;  // already started
   }
 
@@ -821,7 +832,7 @@ static void syncProcessSyncRequest(char *msg, SSyncPeer *pPeer) {
     syncDecPeerRef(pPeer);
   } else {
     pPeer->sstatus = TAOS_SYNC_STATUS_START;
-    sDebug("%s, thread is created to retrieve data", pPeer->id);
+    sDebug("%s, thread is created to retrieve data, set sstatus:%s", pPeer->id, syncStatus[pPeer->sstatus]);
   }
 }
 
@@ -831,9 +842,10 @@ static void syncNotStarted(void *param, void *tmrId) {
 
   pthread_mutex_lock(&pNode->mutex);
   pPeer->timer = NULL;
-  sInfo("%s, sync connection is still not up, restart", pPeer->id);
+  pPeer->sstatus = TAOS_SYNC_STATUS_INIT;
+  sInfo("%s, sync conn is still not up, restart and set sstatus:%s", pPeer->id, syncStatus[pPeer->sstatus]);
   syncRestartConnection(pPeer);
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 }
 
 static void syncTryRecoverFromMaster(void *param, void *tmrId) {
@@ -842,14 +854,14 @@ static void syncTryRecoverFromMaster(void *param, void *tmrId) {
 
   pthread_mutex_lock(&pNode->mutex);
   syncRecoverFromMaster(pPeer);
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 }
 
 static void syncRecoverFromMaster(SSyncPeer *pPeer) {
   SSyncNode *pNode = pPeer->pSyncNode;
 
   if (nodeSStatus != TAOS_SYNC_STATUS_INIT) {
-    sDebug("%s, sync is already started, status:%d", pPeer->id, nodeSStatus);
+    sDebug("%s, sync is already started since sstatus:%s", pPeer->id, syncStatus[nodeSStatus]);
     return;
   }
 
@@ -877,7 +889,7 @@ static void syncRecoverFromMaster(SSyncPeer *pPeer) {
     sError("%s, failed to send sync-req to peer", pPeer->id);
   } else {
     nodeSStatus = TAOS_SYNC_STATUS_START;
-    sInfo("%s, sync-req is sent", pPeer->id);
+    sInfo("%s, sync-req is sent to peer, set sstatus:%s", pPeer->id, syncStatus[nodeSStatus]);
   }
 }
 
@@ -915,7 +927,8 @@ static void syncProcessForwardFromPeer(char *cont, SSyncPeer *pPeer) {
     if (nodeSStatus != TAOS_SYNC_STATUS_INIT) {
       syncSaveIntoBuffer(pPeer, pHead);
     } else {
-      sError("%s, forward discarded, hver:%" PRIu64, pPeer->id, pHead->version);
+      sError("%s, forward discarded since sstatus:%s, hver:%" PRIu64, pPeer->id, syncStatus[nodeSStatus],
+             pHead->version);
     }
   }
 }
@@ -924,8 +937,9 @@ static void syncProcessPeersStatusMsg(char *cont, SSyncPeer *pPeer) {
   SSyncNode *   pNode = pPeer->pSyncNode;
   SPeersStatus *pPeersStatus = (SPeersStatus *)cont;
 
-  sDebug("%s, status msg is received, self:%s sver:%" PRIu64 " peer:%s sver:%" PRIu64 ", ack:%d tranId:%u type:%s", pPeer->id,
-         syncRole[nodeRole], nodeVersion, syncRole[pPeersStatus->role], pPeersStatus->version, pPeersStatus->ack, pPeersStatus->tranId, statusType[pPeersStatus->type]);
+  sDebug("%s, status is received, self:%s:%s:%" PRIu64 ", peer:%s:%" PRIu64 ", ack:%d tranId:%u type:%s pfd:%d",
+         pPeer->id, syncRole[nodeRole], syncStatus[nodeSStatus], nodeVersion, syncRole[pPeersStatus->role],
+         pPeersStatus->version, pPeersStatus->ack, pPeersStatus->tranId, statusType[pPeersStatus->type], pPeer->peerFd);
 
   pPeer->version = pPeersStatus->version;
   syncCheckRole(pPeer, pPeersStatus->peersStatus, pPeersStatus->role);
@@ -982,7 +996,7 @@ static int32_t syncProcessPeerMsg(void *param, void *buffer) {
     }
   }
 
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 
   return code;
 }
@@ -1014,8 +1028,10 @@ static void syncSendPeersStatusMsgToPeer(SSyncPeer *pPeer, char ack, int8_t type
 
   int32_t retLen = taosWriteMsg(pPeer->peerFd, msg, statusMsgLen);
   if (retLen == statusMsgLen) {
-    sDebug("%s, status msg is sent, self:%s sver:%" PRIu64 ", ack:%d tranId:%u type:%s", pPeer->id, syncRole[pPeersStatus->role],
-           pPeersStatus->version, pPeersStatus->ack, pPeersStatus->tranId, statusType[pPeersStatus->type]);
+    sDebug("%s, status is sent, self:%s:%s:%" PRIu64 ", peer:%s:%s:%" PRIu64 ", ack:%d tranId:%u type:%s pfd:%d",
+           pPeer->id, syncRole[nodeRole], syncStatus[nodeSStatus], nodeVersion, syncRole[pPeer->role],
+           syncStatus[pPeer->sstatus], pPeer->version, pPeersStatus->ack, pPeersStatus->tranId,
+           statusType[pPeersStatus->type], pPeer->peerFd);
   } else {
     sDebug("%s, failed to send status msg, restart", pPeer->id);
     syncRestartConnection(pPeer);
@@ -1048,7 +1064,7 @@ static void syncSetupPeerConnection(SSyncPeer *pPeer) {
   firstPkt.sourceId = pNode->vgId;  // tell arbitrator its vgId
 
   if (taosWriteMsg(connFd, &firstPkt, sizeof(firstPkt)) == sizeof(firstPkt)) {
-    sDebug("%s, connection to peer server is setup", pPeer->id);
+    sDebug("%s, connection to peer server is setup, pfd:%d sfd:%d", pPeer->id, connFd, pPeer->syncFd);
     pPeer->peerFd = connFd;
     pPeer->role = TAOS_SYNC_ROLE_UNSYNCED;
     pPeer->pConn = taosAllocateTcpConn(tsTcpPool, pPeer, connFd);
@@ -1069,7 +1085,7 @@ static void syncCheckPeerConnection(void *param, void *tmrId) {
   sDebug("%s, check peer connection", pPeer->id);
   syncSetupPeerConnection(pPeer);
 
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 }
 
 static void syncCreateRestoreDataThread(SSyncPeer *pPeer) {
@@ -1135,7 +1151,8 @@ static void syncProcessIncommingConnection(int32_t connFd, uint32_t sourceIp) {
       pPeer->syncFd = connFd;
       syncCreateRestoreDataThread(pPeer);
     } else {
-      sDebug("%s, TCP connection is already up, close one", pPeer->id);
+      sDebug("%s, TCP connection is already up(pfd:%d), close one, new pfd:%d sfd:%d", pPeer->id, pPeer->peerFd, connFd,
+             pPeer->syncFd);
       syncClosePeerConn(pPeer);
       pPeer->peerFd = connFd;
       pPeer->pConn = taosAllocateTcpConn(tsTcpPool, pPeer, connFd);
@@ -1145,7 +1162,7 @@ static void syncProcessIncommingConnection(int32_t connFd, uint32_t sourceIp) {
     }
   }
 
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 }
 
 static void syncProcessBrokenLink(void *param) {
@@ -1156,14 +1173,14 @@ static void syncProcessBrokenLink(void *param) {
   if (taosAcquireRef(tsSyncRefId, pNode->rid) == NULL) return;
   pthread_mutex_lock(&pNode->mutex);
 
-  sDebug("%s, TCP link is broken since %s", pPeer->id, strerror(errno));
+  sDebug("%s, TCP link is broken since %s, pfd:%d sfd:%d", pPeer->id, strerror(errno), pPeer->peerFd, pPeer->syncFd);
   pPeer->peerFd = -1;
 
   if (syncDecPeerRef(pPeer) != 0) {
     syncRestartConnection(pPeer);
   }
 
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
   taosReleaseRef(tsSyncRefId, pNode->rid);
 }
 
@@ -1239,10 +1256,13 @@ static void syncMonitorNodeRole(void *param, void *tmrId) {
     if (index == pNode->selfIndex) continue;
 
     SSyncPeer *pPeer = pNode->peerInfo[index];
-    if (pPeer->role > TAOS_SYNC_ROLE_UNSYNCED && nodeRole > TAOS_SYNC_ROLE_UNSYNCED) continue;
-    if (pPeer->sstatus > TAOS_SYNC_STATUS_INIT || nodeSStatus > TAOS_SYNC_STATUS_INIT) continue;
+    if (/*pPeer->role > TAOS_SYNC_ROLE_UNSYNCED && */ nodeRole > TAOS_SYNC_ROLE_UNSYNCED) continue;
+    if (/*pPeer->sstatus > TAOS_SYNC_STATUS_INIT || */ nodeSStatus > TAOS_SYNC_STATUS_INIT) continue;
 
+    sDebug("%s, check roles since self:%s sstatus:%s, peer:%s sstatus:%s", pPeer->id, syncRole[pPeer->role],
+           syncStatus[pPeer->sstatus], syncRole[nodeRole], syncStatus[nodeSStatus]);
     syncSendPeersStatusMsgToPeer(pPeer, 1, SYNC_STATUS_CHECK_ROLE, syncGenTranId());
+    break;
   }
 
   pNode->pRoleTimer = taosTmrStart(syncMonitorNodeRole, SYNC_ROLE_TIMER, (void *)pNode->rid, tsSyncTmrCtrl);
@@ -1271,7 +1291,7 @@ static void syncMonitorFwdInfos(void *param, void *tmrId) {
       }
 
       syncRemoveConfirmedFwdInfo(pNode);
-      pthread_mutex_unlock(&(pNode->mutex));
+      pthread_mutex_unlock(&pNode->mutex);
     }
 
     pNode->pFwdTimer = taosTmrStart(syncMonitorFwdInfos, SYNC_FWD_TIMER, (void *)pNode->rid, tsSyncTmrCtrl);
@@ -1339,7 +1359,7 @@ static int32_t syncForwardToPeerImpl(SSyncNode *pNode, void *data, void *mhandle
     }
   }
 
-  pthread_mutex_unlock(&(pNode->mutex));
+  pthread_mutex_unlock(&pNode->mutex);
 
   return code;
 }
diff --git a/src/sync/src/syncRestore.c b/src/sync/src/syncRestore.c
index b31ec5f7c7..2ca4b5424e 100644
--- a/src/sync/src/syncRestore.c
+++ b/src/sync/src/syncRestore.c
@@ -65,7 +65,10 @@ static int32_t syncRestoreFile(SSyncPeer *pPeer, uint64_t *fversion) {
   while (1) {
     // read file info
     int32_t ret = taosReadMsg(pPeer->syncFd, &(minfo), sizeof(minfo));
-    if (ret < 0) break;
+    if (ret < 0) {
+      sError("%s, failed to read file info while restore file since %s", pPeer->id, strerror(errno));
+      break;
+    }
 
     // if no more file from master, break;
     if (minfo.name[0] == 0 || minfo.magic == 0) {
@@ -83,7 +86,7 @@ static int32_t syncRestoreFile(SSyncPeer *pPeer, uint64_t *fversion) {
 
     // check the file info
     sinfo = minfo;
-    sDebug("%s, get file info:%s", pPeer->id, minfo.name);
+    sDebug("%s, get file:%s info size:%" PRId64, pPeer->id, minfo.name, minfo.size);
     sinfo.magic = (*pNode->getFileInfo)(pNode->vgId, sinfo.name, &sinfo.index, TAOS_SYNC_MAX_INDEX, &sinfo.size,
                                         &sinfo.fversion);
 
@@ -92,8 +95,11 @@ static int32_t syncRestoreFile(SSyncPeer *pPeer, uint64_t *fversion) {
     fileAck.sync = (sinfo.magic != minfo.magic || sinfo.name[0] == 0) ? 1 : 0;
 
     // send file ack
-    ret = taosWriteMsg(pPeer->syncFd, &(fileAck), sizeof(fileAck));
-    if (ret < 0) break;
+    ret = taosWriteMsg(pPeer->syncFd, &fileAck, sizeof(fileAck));
+    if (ret < 0) {
+      sError("%s, failed to write file:%s ack while restore file since %s", pPeer->id, minfo.name, strerror(errno));
+      break;
+    }
 
     // if sync is not required, continue
     if (fileAck.sync == 0) {
@@ -108,14 +114,17 @@ static int32_t syncRestoreFile(SSyncPeer *pPeer, uint64_t *fversion) {
 
     int32_t dfd = open(name, O_WRONLY | O_CREAT | O_TRUNC, S_IRWXU | S_IRWXG | S_IRWXO);
     if (dfd < 0) {
-      sError("%s, failed to open file:%s", pPeer->id, name);
+      sError("%s, failed to open file:%s while restore file since %s", pPeer->id, minfo.name, strerror(errno));
       break;
     }
 
     ret = taosCopyFds(pPeer->syncFd, dfd, minfo.size);
     fsync(dfd);
     close(dfd);
-    if (ret < 0) break;
+    if (ret < 0) {
+      sError("%s, failed to copy file:%s while restore file since %s", pPeer->id, minfo.name, strerror(errno));
+      break;
+    }
 
     fileChanged = true;
     sDebug("%s, %s is received, size:%" PRId64, pPeer->id, minfo.name, minfo.size);
@@ -125,6 +134,7 @@ static int32_t syncRestoreFile(SSyncPeer *pPeer, uint64_t *fversion) {
     // data file is changed, code shall be set to 1
     *fversion = minfo.fversion;
     code = 1;
+    sDebug("%s, file changed while restore file", pPeer->id);
   }
 
   if (code < 0) {
@@ -146,15 +156,22 @@ static int32_t syncRestoreWal(SSyncPeer *pPeer) {
 
   while (1) {
     ret = taosReadMsg(pPeer->syncFd, pHead, sizeof(SWalHead));
-    if (ret < 0) break;
+    if (ret < 0) {
+      sError("%s, failed to read walhead while restore wal since %s", pPeer->id, strerror(errno));
+      break;
+    }
 
     if (pHead->len == 0) {
+      sDebug("%s, wal is synced over", pPeer->id);
       code = 0;
       break;
     }  // wal sync over
 
     ret = taosReadMsg(pPeer->syncFd, pHead->cont, pHead->len);
-    if (ret < 0) break;
+    if (ret < 0) {
+      sError("%s, failed to read walcont, len:%d while restore wal since %s", pPeer->id, pHead->len, strerror(errno));
+      break;
+    }
 
     sTrace("%s, restore a record, qtype:wal len:%d hver:%" PRIu64, pPeer->id, pHead->len, pHead->version);
 
@@ -267,7 +284,7 @@ static int32_t syncRestoreDataStepByStep(SSyncPeer *pPeer) {
   nodeSStatus = TAOS_SYNC_STATUS_FILE;
   uint64_t fversion = 0;
 
-  sDebug("%s, start to restore file", pPeer->id);
+  sDebug("%s, start to restore file, set sstatus:%s", pPeer->id, syncStatus[nodeSStatus]);
   int32_t code = syncRestoreFile(pPeer, &fversion);
   if (code < 0) {
     sError("%s, failed to restore file", pPeer->id);
@@ -291,7 +308,7 @@ static int32_t syncRestoreDataStepByStep(SSyncPeer *pPeer) {
   }
 
   nodeSStatus = TAOS_SYNC_STATUS_CACHE;
-  sDebug("%s, start to insert buffered points", pPeer->id);
+  sDebug("%s, start to insert buffered points, set sstatus:%s", pPeer->id, syncStatus[nodeSStatus]);
   if (syncProcessBufferedFwd(pPeer) < 0) {
     sError("%s, failed to insert buffered points", pPeer->id);
     return -1;
@@ -327,6 +344,8 @@ void *syncRestoreData(void *param) {
   (*pNode->notifyRole)(pNode->vgId, nodeRole);
 
   nodeSStatus = TAOS_SYNC_STATUS_INIT;
+  sInfo("%s, sync over, set sstatus:%s", pPeer->id, syncStatus[nodeSStatus]);
+
   taosClose(pPeer->syncFd);
   syncCloseRecvBuffer(pNode);
   __sync_fetch_and_sub(&tsSyncNum, 1);
diff --git a/src/sync/src/syncRetrieve.c b/src/sync/src/syncRetrieve.c
index b6dacaa262..58d09d080e 100644
--- a/src/sync/src/syncRetrieve.c
+++ b/src/sync/src/syncRetrieve.c
@@ -114,7 +114,10 @@ static int32_t syncRetrieveFile(SSyncPeer *pPeer) {
 
     // send the file info
     int32_t ret = taosWriteMsg(pPeer->syncFd, &(fileInfo), sizeof(fileInfo));
-    if (ret < 0) break;
+    if (ret < 0) {
+      sError("%s, failed to write file:%s info while retrieve file since %s", pPeer->id, fileInfo.name, strerror(errno));
+      break;
+    }
 
     // if no file anymore, break
     if (fileInfo.magic == 0 || fileInfo.name[0] == 0) {
@@ -124,8 +127,11 @@ static int32_t syncRetrieveFile(SSyncPeer *pPeer) {
     }
 
     // wait for the ack from peer
-    ret = taosReadMsg(pPeer->syncFd, &(fileAck), sizeof(fileAck));
-    if (ret < 0) break;
+    ret = taosReadMsg(pPeer->syncFd, &fileAck, sizeof(fileAck));
+    if (ret < 0) {
+      sError("%s, failed to read file:%s ack while retrieve file since %s", pPeer->id, fileInfo.name, strerror(errno));
+      break;
+    }
 
     // set the peer sync version
     pPeer->sversion = fileInfo.fversion;
@@ -134,7 +140,10 @@ static int32_t syncRetrieveFile(SSyncPeer *pPeer) {
     snprintf(name, sizeof(name), "%s/%s", pNode->path, fileInfo.name);
 
     // add the file into watch list
-    if (syncAddIntoWatchList(pPeer, name) < 0) break;
+    if (syncAddIntoWatchList(pPeer, name) < 0) {
+      sError("%s, failed to watch file:%s while retrieve file since %s", pPeer->id, fileInfo.name, strerror(errno));
+      break;
+    }
 
     // if sync is not required, continue
     if (fileAck.sync == 0) {
@@ -145,21 +154,30 @@ static int32_t syncRetrieveFile(SSyncPeer *pPeer) {
 
     // send the file to peer
     int32_t sfd = open(name, O_RDONLY);
-    if (sfd < 0) break;
+    if (sfd < 0) {
+      sError("%s, failed to open file:%s while retrieve file since %s", pPeer->id, fileInfo.name, strerror(errno));
+      break;
+    }
 
     ret = taosSendFile(pPeer->syncFd, sfd, NULL, fileInfo.size);
     close(sfd);
-    if (ret < 0) break;
+    if (ret < 0) {
+      sError("%s, failed to send file:%s while retrieve file since %s", pPeer->id, fileInfo.name, strerror(errno));
+      break;
+    }
 
     sDebug("%s, %s is sent, size:%" PRId64, pPeer->id, name, fileInfo.size);
     fileInfo.index++;
 
     // check if processed files are modified
-    if (syncAreFilesModified(pPeer) != 0) break;
+    if (syncAreFilesModified(pPeer) != 0) {
+      sInfo("%s, file:%s are modified while retrieve file since %s", pPeer->id, fileInfo.name, strerror(errno));
+      break;
+    }
   }
 
   if (code < 0) {
-    sError("%s, failed to retrieve file since %s", pPeer->id, strerror(errno));
+    sError("%s, failed to retrieve file", pPeer->id);
   }
 
   return code;
@@ -318,6 +336,7 @@ static int32_t syncProcessLastWal(SSyncPeer *pPeer, char *wname, int64_t index)
       if (((event & IN_MODIFY) == 0) || once) {
         if (fversion == 0) {
           pPeer->sstatus = TAOS_SYNC_STATUS_CACHE;  // start to forward pkt
+          sDebug("%s, fversion is 0 then set sstatus:%s", pPeer->id, syncStatus[pPeer->sstatus]);
           fversion = nodeVersion;                   // must read data to fversion
         }
       }
@@ -416,8 +435,9 @@ static int32_t syncRetrieveWal(SSyncPeer *pPeer) {
   }
 
   if (code == 0) {
-    sInfo("%s, wal retrieve is finished", pPeer->id);
     pPeer->sstatus = TAOS_SYNC_STATUS_CACHE;
+    sInfo("%s, wal retrieve is finished, set sstatus:%s", pPeer->id, syncStatus[pPeer->sstatus]);
+
     SWalHead walHead;
     memset(&walHead, 0, sizeof(walHead));
     code = taosWriteMsg(pPeer->syncFd, &walHead, sizeof(walHead));
@@ -445,7 +465,7 @@ static int32_t syncRetrieveDataStepByStep(SSyncPeer *pPeer) {
 
   pPeer->sversion = 0;
   pPeer->sstatus = TAOS_SYNC_STATUS_FILE;
-  sInfo("%s, start to retrieve file", pPeer->id);
+  sInfo("%s, start to retrieve file, set sstatus:%s", pPeer->id, syncStatus[pPeer->sstatus]);
   if (syncRetrieveFile(pPeer) < 0) {
     sError("%s, failed to retrieve file", pPeer->id);
     return -1;
diff --git a/src/util/src/tsocket.c b/src/util/src/tsocket.c
index 1be79b7bbd..2543c81708 100644
--- a/src/util/src/tsocket.c
+++ b/src/util/src/tsocket.c
@@ -107,7 +107,7 @@ int32_t taosWriteMsg(SOCKET fd, void *buf, int32_t nbytes) {
   while (nleft > 0) {
     nwritten = (int32_t)taosWriteSocket(fd, (char *)ptr, (size_t)nleft);
     if (nwritten <= 0) {
-      if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)
+      if (errno == EINTR /* || errno == EAGAIN || errno == EWOULDBLOCK */)
         continue;
       else
         return -1;
@@ -133,7 +133,7 @@ int32_t taosReadMsg(SOCKET fd, void *buf, int32_t nbytes) {
     if (nread == 0) {
       break;
     } else if (nread < 0) {
-      if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK) {
+      if (errno == EINTR/* || errno == EAGAIN || errno == EWOULDBLOCK*/) {
         continue;
       } else {
         return -1;
diff --git a/tests/pytest/cluster/clusterSetup.py b/tests/pytest/cluster/clusterSetup.py
index 36af8ac42e..dbda5657b6 100644
--- a/tests/pytest/cluster/clusterSetup.py
+++ b/tests/pytest/cluster/clusterSetup.py
@@ -31,6 +31,23 @@ class Node:
         self.homeDir = homeDir
         self.conn = Connection("{}@{}".format(username, hostName), connect_kwargs={"password": "{}".format(password)}) 
     
+    def buildTaosd(self):
+        try:
+            self.conn.cd("/root/TDinternal/community")
+            self.conn.run("git checkout develop")
+            self.conn.run("git pull")
+            self.conn.cd("/root/TDinternal")
+            self.conn.run("git checkout develop")
+            self.conn.run("git pull")
+            self.conn.cd("/root/TDinternal/debug")
+            self.conn.run("cmake ..")
+            self.conn.run("make")
+            self.conn.run("make install")
+        except Exception as e:
+            print("Build Taosd error for node %d " % self.index)
+            logging.exception(e)
+            pass
+
     def startTaosd(self):
         try:
             self.conn.run("sudo systemctl start taosd")
@@ -50,7 +67,7 @@ class Node:
             self.conn.run("sudo systemctl restart taosd")
         except Exception as e:
             print("Stop Taosd error for node %d " % self.index)
-            logging.exception(e)
+            logging.exception(e)    
 
     def removeTaosd(self):
         try:
@@ -105,9 +122,11 @@ class Node:
 
 class Nodes:
     def __init__(self):
-        self.node1 = Node(1, 'ubuntu', '192.168.1.52', 'node1', 'tbase125!', '/home/ubuntu')
-        self.node2 = Node(2, 'ubuntu', '192.168.1.53', 'node2', 'tbase125!', '/home/ubuntu')
-        self.node3 = Node(3, 'ubuntu', '192.168.1.54', 'node3', 'tbase125!', '/home/ubuntu')
+        self.node1 = Node(1, 'root', '52.151.60.239', 'node1', 'r', '/root/')
+        self.node2 = Node(2, 'root', '52.183.32.246', 'node1', 'r', '/root/')
+        self.node3 = Node(3, 'root', '51.143.46.79', 'node1', 'r', '/root/')
+        self.node4 = Node(4, 'root', '52.183.2.76', 'node1', 'r', '/root/')
+        self.node5 = Node(5, 'root', '13.66.225.87', 'node1', 'r', '/root/')        
 
     def stopAllTaosd(self):
         self.node1.stopTaosd()
diff --git a/tests/pytest/query/queryJoin.py b/tests/pytest/query/queryJoin.py
index 5ad49a265e..57b7e8868d 100644
--- a/tests/pytest/query/queryJoin.py
+++ b/tests/pytest/query/queryJoin.py
@@ -141,6 +141,40 @@ class TDTestCase:
         tdSql.query("select * from meters1, meters3 where meters1.ts = meters3.ts and meters1.tag1 = meters3.tag1")
         tdSql.checkRows(0)
 
+        tdSql.execute("create table join_mt0(ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool, c8 binary(10), c9 nchar(9)) tags(t1 int, t2 binary(12))")
+        tdSql.execute("create table join_mt1(ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool, c8 binary(10), c9 nchar(9)) tags(t1 int, t2 binary(12), t3 int)")
+
+        ts = 1538548685000
+        for i in range(3):
+            tdSql.execute("create table join_tb%d using join_mt0 tags(%d, 'abc')" % (i, i)) 
+            sql = "insert into join_tb%d values" % i
+            for j in range(500):
+                val = j % 100
+                sql += "(%d, %d, %f, %d, %d, %d, %f, %d, 'binary%d', 'nchar%d')" % (ts + j, val, val * 1.0, val, val, val, val * 1.0, val % 2,  val, val)
+            tdSql.execute(sql)
+            sql = "insert into join_tb%d values" % i
+            for j in range(500, 1000):
+                val = j % 100
+                sql += "(%d, %d, %f, %d, %d, %d, %f, %d, 'binary%d', 'nchar%d')" % (ts + 500 + j, val, val * 1.0, val, val, val, val * 1.0, val % 2,  val, val)
+            tdSql.execute(sql)
+        
+        for i in range(3):
+            tdSql.execute("create table join_1_tb%d using join_mt1 tags(%d, 'abc%d', %d)" % (i, i, i, i))            
+            sql = "insert into join_1_tb%d values" % i
+            for j in range(500):
+                val = j % 100
+                sql += "(%d, %d, %f, %d, %d, %d, %f, %d, 'binary%d', 'nchar%d')" % (ts + j, val, val * 1.0, val, val, val, val * 1.0, val % 2,  val, val)
+            tdSql.execute(sql)
+            sql = "insert into join_1_tb%d values" % i
+            for j in range(500, 1000):
+                val = j % 100
+                sql += "(%d, %d, %f, %d, %d, %d, %f, %d, 'binary%d', 'nchar%d')" % (ts + 500 + j, val, val * 1.0, val, val, val, val * 1.0, val % 2,  val, val)
+            tdSql.execute(sql)
+
+        tdSql.error("select count(join_mt0.c1), sum(join_mt1.c2), first(join_mt0.c5), last(join_mt1.c7) 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 order by join_mt0.ts desc")
+        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;")
 
     def stop(self):
         tdSql.close()
diff --git a/tests/script/general/parser/col_arithmetic_operation.sim b/tests/script/general/parser/col_arithmetic_operation.sim
index d5ba57e6c7..7adae8ef81 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
@@ -28,12 +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
@@ -46,50 +76,61 @@ 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
 
-##### 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
+  $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 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
+    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
 
-#### illegal operations
+#endw
+
+#=================================== above are setup test environment =============================
+run general/parser/col_arithmetic_query.sim
+
+#======================================= 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
+
+print ================== server restart completed
+sql connect
+sleep 500c
+
+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 +149,4 @@ 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 $data05 != 9.000000000 then
-  return -1
-endi
-
-sql_error select first(c1, c2) - last(c1, c2) from stb interval(1y)
-sql_error select first(ts) - last(ts) from stb interval(1y)
-sql_error select top(c1, 2) - last(c1) from stb;
-sql_error select stddev(c1) - last(c1) from stb;
-sql_error select diff(c1) - last(c1) from stb;
-sql_error select first(c7) - last(c7) from stb;
-sql_error select first(c8) - last(c8) from stb;
-sql_error select first(c9) - last(c9) from stb;
-
 system sh/exec.sh -n dnode1 -s stop -x SIGINT
\ No newline at end of file
diff --git a/tests/script/general/parser/col_arithmetic_query.sim b/tests/script/general/parser/col_arithmetic_query.sim
new file mode 100644
index 0000000000..408b039144
--- /dev/null
+++ b/tests/script/general/parser/col_arithmetic_query.sim
@@ -0,0 +1,478 @@
+# ======================================= query test cases ========================================
+# select from table
+
+$dbPrefix = ca_db
+$tbPrefix = ca_tb
+$stbPrefix = ca_stb
+$rowNum = 10000
+
+$i = 0
+$db = $dbPrefix . $i
+sql use $db
+
+$tb = $tbPrefix . 0
+$stb = $stbPrefix . $i
+
+## 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;
+if $rows != 10000 then
+  return -1
+endi
+
+if $data00 != 0.000000000 then
+  return -1
+endi
+
+if $data01 != -nan then
+  print expect -nan, actual: $data01
+  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
+
+if $data00 != 0.100000000 then
+  print expect 0.100000000, acutal:$data00
+  return -1
+endi
+
+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 $data20 != 20.250000000 then
+  print expect 20.250000000, acutal:$data21
+  return -1
+endi
+
+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
+  return -1
+endi
+
+# no result return [d.3]
+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] =================================================
+# not available
+
+# error cases
+# not available
+
+# multi row result aggregation [d.4]
+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*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
+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
+
+# 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 * c1 + 12 from $tb limit 12 offset 99;
+if $rows != 12 then
+ return -1
+endi
+
+if $data00 != 93.000000000 then
+  return -1
+endi
+
+if $data90 != 76.000000000 then
+  return -1
+endi
+
+sql select c4 / 99.123 from $tb limit 10 offset 9999;
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 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%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 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
+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, 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;
+if $rows != 1 then
+  return -1
+endi
+
+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 >
+
+# 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 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
+
+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