diff --git a/source/client/inc/clientInt.h b/source/client/inc/clientInt.h
index 96d7cead68..f244059b7c 100644
--- a/source/client/inc/clientInt.h
+++ b/source/client/inc/clientInt.h
@@ -238,9 +238,9 @@ void initMsgHandleFp();
 TAOS* taos_connect_internal(const char* ip, const char* user, const char* pass, const char* auth, const char* db,
                             uint16_t port);
 
-void* doFetchRow(SRequestObj* pRequest, bool setupOneRowPtr);
+void* doFetchRow(SRequestObj* pRequest, bool setupOneRowPtr, bool convertUcs4);
 
-int32_t setResultDataPtr(SReqResultInfo* pResultInfo, TAOS_FIELD* pFields, int32_t numOfCols, int32_t numOfRows);
+int32_t setResultDataPtr(SReqResultInfo* pResultInfo, TAOS_FIELD* pFields, int32_t numOfCols, int32_t numOfRows, bool convertUcs4);
 
 int32_t buildRequest(STscObj* pTscObj, const char* sql, int sqlLen, SRequestObj** pRequest);
 
diff --git a/source/client/src/clientImpl.c b/source/client/src/clientImpl.c
index b311060ea9..c396ab40ac 100644
--- a/source/client/src/clientImpl.c
+++ b/source/client/src/clientImpl.c
@@ -13,7 +13,7 @@
 static int32_t       initEpSetFromCfg(const char* firstEp, const char* secondEp, SCorEpSet* pEpSet);
 static SMsgSendInfo* buildConnectMsg(SRequestObj* pRequest);
 static void          destroySendMsgInfo(SMsgSendInfo* pMsgBody);
-static int32_t       setQueryResultFromRsp(SReqResultInfo* pResultInfo, const SRetrieveTableRsp* pRsp);
+static int32_t       setQueryResultFromRsp(SReqResultInfo* pResultInfo, const SRetrieveTableRsp* pRsp, bool convertUcs4);
 
 static bool stringLengthCheck(const char* str, size_t maxsize) {
   if (str == NULL) {
@@ -176,7 +176,7 @@ int32_t execLocalCmd(SRequestObj* pRequest, SQuery* pQuery) {
   SRetrieveTableRsp* pRsp = NULL;
   int32_t code = qExecCommand(pQuery->pRoot, &pRsp);
   if (TSDB_CODE_SUCCESS == code && NULL != pRsp) {
-    code = setQueryResultFromRsp(&pRequest->body.resInfo, pRsp);
+    code = setQueryResultFromRsp(&pRequest->body.resInfo, pRsp, false);
   }
   return code;
 }
@@ -616,7 +616,7 @@ static void doSetOneRowPtr(SReqResultInfo* pResultInfo) {
   }
 }
 
-void* doFetchRow(SRequestObj* pRequest, bool setupOneRowPtr) {
+void* doFetchRow(SRequestObj* pRequest, bool setupOneRowPtr, bool convertUcs4) {
   assert(pRequest != NULL);
   SReqResultInfo* pResultInfo = &pRequest->body.resInfo;
 
@@ -637,7 +637,7 @@ void* doFetchRow(SRequestObj* pRequest, bool setupOneRowPtr) {
         return NULL;
       }
 
-      pRequest->code = setQueryResultFromRsp(&pRequest->body.resInfo, (SRetrieveTableRsp*)pResInfo->pData);
+      pRequest->code = setQueryResultFromRsp(&pRequest->body.resInfo, (SRetrieveTableRsp*)pResInfo->pData, convertUcs4);
       if (pRequest->code != TSDB_CODE_SUCCESS) {
         pResultInfo->numOfRows = 0;
         return NULL;
@@ -735,7 +735,42 @@ static int32_t doPrepareResPtr(SReqResultInfo* pResInfo) {
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t setResultDataPtr(SReqResultInfo* pResultInfo, TAOS_FIELD* pFields, int32_t numOfCols, int32_t numOfRows) {
+static int32_t doConvertUCS4(SReqResultInfo* pResultInfo, int32_t numOfRows, int32_t numOfCols, int32_t* colLength) {
+  for (int32_t i = 0; i < numOfCols; ++i) {
+    int32_t type = pResultInfo->fields[i].type;
+    int32_t bytes = pResultInfo->fields[i].bytes;
+
+    if (type == TSDB_DATA_TYPE_NCHAR) {
+      char* p = taosMemoryRealloc(pResultInfo->convertBuf[i], colLength[i]);
+      if (p == NULL) {
+        return TSDB_CODE_OUT_OF_MEMORY;
+      }
+
+      pResultInfo->convertBuf[i] = p;
+
+      SResultColumn* pCol = &pResultInfo->pCol[i];
+      for (int32_t j = 0; j < numOfRows; ++j) {
+        if (pCol->offset[j] != -1) {
+          char* pStart = pCol->offset[j] + pCol->pData;
+
+          int32_t len = taosUcs4ToMbs((TdUcs4*)varDataVal(pStart), varDataLen(pStart), varDataVal(p));
+          ASSERT(len <= bytes);
+
+          varDataSetLen(p, len);
+          pCol->offset[j] = (p - pResultInfo->convertBuf[i]);
+          p += (len + VARSTR_HEADER_SIZE);
+        }
+      }
+
+      pResultInfo->pCol[i].pData = pResultInfo->convertBuf[i];
+      pResultInfo->row[i] = pResultInfo->pCol[i].pData;
+    }
+  }
+
+  return TSDB_CODE_SUCCESS;
+}
+
+int32_t setResultDataPtr(SReqResultInfo* pResultInfo, TAOS_FIELD* pFields, int32_t numOfCols, int32_t numOfRows, bool convertUcs4) {
   assert(numOfCols > 0 && pFields != NULL && pResultInfo != NULL);
   if (numOfRows == 0) {
     return TSDB_CODE_SUCCESS;
@@ -767,37 +802,11 @@ int32_t setResultDataPtr(SReqResultInfo* pResultInfo, TAOS_FIELD* pFields, int32
   }
 
   // convert UCS4-LE encoded character to native multi-bytes character in current data block.
-  for (int32_t i = 0; i < numOfCols; ++i) {
-    int32_t type = pResultInfo->fields[i].type;
-    int32_t bytes = pResultInfo->fields[i].bytes;
-
-    if (type == TSDB_DATA_TYPE_NCHAR) {
-      char* p = taosMemoryRealloc(pResultInfo->convertBuf[i], colLength[i]);
-      if (p == NULL) {
-        return TSDB_CODE_OUT_OF_MEMORY;
-      }
-      pResultInfo->convertBuf[i] = p;
-
-      SResultColumn* pCol = &pResultInfo->pCol[i];
-      for (int32_t j = 0; j < numOfRows; ++j) {
-        if (pCol->offset[j] != -1) {
-          pStart = pCol->offset[j] + pCol->pData;
-
-          int32_t len = taosUcs4ToMbs((TdUcs4*)varDataVal(pStart), varDataLen(pStart), varDataVal(p));
-          ASSERT(len <= bytes);
-
-          varDataSetLen(p, len);
-          pCol->offset[j] = (p - pResultInfo->convertBuf[i]);
-          p += (len + VARSTR_HEADER_SIZE);
-        }
-      }
-
-      pResultInfo->pCol[i].pData = pResultInfo->convertBuf[i];
-      pResultInfo->row[i] = pResultInfo->pCol[i].pData;
-    }
+  if (convertUcs4) {
+    code = doConvertUCS4(pResultInfo, numOfRows, numOfCols, colLength);
   }
 
-  return TSDB_CODE_SUCCESS;
+  return code;
 }
 
 char* getDbOfConnection(STscObj* pObj) {
@@ -829,7 +838,7 @@ void resetConnectDB(STscObj* pTscObj) {
   taosThreadMutexUnlock(&pTscObj->mutex);
 }
 
-int32_t setQueryResultFromRsp(SReqResultInfo* pResultInfo, const SRetrieveTableRsp* pRsp) {
+int32_t setQueryResultFromRsp(SReqResultInfo* pResultInfo, const SRetrieveTableRsp* pRsp, bool convertUcs4) {
   assert(pResultInfo != NULL && pRsp != NULL);
 
   pResultInfo->pRspMsg    = (const char*)pRsp;
@@ -842,5 +851,5 @@ int32_t setQueryResultFromRsp(SReqResultInfo* pResultInfo, const SRetrieveTableR
 
   // TODO handle the compressed case
   pResultInfo->totalRows += pResultInfo->numOfRows;
-  return setResultDataPtr(pResultInfo, pResultInfo->fields, pResultInfo->numOfCols, pResultInfo->numOfRows);
+  return setResultDataPtr(pResultInfo, pResultInfo->fields, pResultInfo->numOfCols, pResultInfo->numOfRows, convertUcs4);
 }
diff --git a/source/client/src/clientMain.c b/source/client/src/clientMain.c
index e10cf5179e..51629510d0 100644
--- a/source/client/src/clientMain.c
+++ b/source/client/src/clientMain.c
@@ -168,7 +168,7 @@ TAOS_ROW taos_fetch_row(TAOS_RES *res) {
     return NULL;
   }
 
-  return doFetchRow(pRequest, true);
+  return doFetchRow(pRequest, true, true);
 }
 
 int taos_print_row(char *str, TAOS_ROW row, TAOS_FIELD *fields, int num_fields) {
@@ -404,7 +404,7 @@ int taos_fetch_block_s(TAOS_RES *res, int* numOfRows, TAOS_ROW *rows) {
     return 0;
   }
 
-  doFetchRow(pRequest, false);
+  doFetchRow(pRequest, false, true);
 
   // TODO refactor
   SReqResultInfo *pResultInfo = &pRequest->body.resInfo;
@@ -426,7 +426,7 @@ int taos_fetch_raw_block(TAOS_RES *res, int* numOfRows, void** pData) {
     return 0;
   }
 
-  doFetchRow(pRequest, false);
+  doFetchRow(pRequest, false, false);
 
   SReqResultInfo *pResultInfo = &pRequest->body.resInfo;
 
diff --git a/source/client/src/clientMsgHandler.c b/source/client/src/clientMsgHandler.c
index 4314391743..99c6e81551 100644
--- a/source/client/src/clientMsgHandler.c
+++ b/source/client/src/clientMsgHandler.c
@@ -191,7 +191,7 @@ int32_t processRetrieveMnodeRsp(void* param, const SDataBuf* pMsg, int32_t code)
   pResInfo->completed = pRetrieve->completed;
 
   pResInfo->current = 0;
-  setResultDataPtr(pResInfo, pResInfo->fields, pResInfo->numOfCols, pResInfo->numOfRows);
+//  setResultDataPtr(pResInfo, pResInfo->fields, pResInfo->numOfCols, pResInfo->numOfRows);
 
   tscDebug("0x%"PRIx64" numOfRows:%d, complete:%d, qId:0x%"PRIx64, pRequest->self, pRetrieve->numOfRows,
            pRetrieve->completed, pRequest->body.showInfo.execId);
@@ -225,7 +225,7 @@ int32_t processRetrieveVndRsp(void* param, const SDataBuf* pMsg, int32_t code) {
   pResInfo->pData     = pFetchRsp->data;
 
   pResInfo->current = 0;
-  setResultDataPtr(pResInfo, pResInfo->fields, pResInfo->numOfCols, pResInfo->numOfRows);
+//  setResultDataPtr(pResInfo, pResInfo->fields, pResInfo->numOfCols, pResInfo->numOfRows);
 
   tscDebug("0x%"PRIx64" numOfRows:%d, complete:%d, qId:0x%"PRIx64, pRequest->self, pFetchRsp->numOfRows,
            pFetchRsp->completed, pRequest->body.showInfo.execId);
diff --git a/source/libs/executor/inc/executorimpl.h b/source/libs/executor/inc/executorimpl.h
index f6f863c82d..9fee599a5d 100644
--- a/source/libs/executor/inc/executorimpl.h
+++ b/source/libs/executor/inc/executorimpl.h
@@ -232,9 +232,11 @@ typedef struct STaskAttr {
 } STaskAttr;
 
 struct SOperatorInfo;
+struct SAggSupporter;
+struct SOptrBasicInfo;
 
-typedef void (*__optr_encode_fn_t)(struct SOperatorInfo* pOperator, char **result, int32_t *length);
-typedef bool (*__optr_decode_fn_t)(struct SOperatorInfo* pOperator, char *result, int32_t length);
+typedef void (*__optr_encode_fn_t)(struct SOperatorInfo* pOperator, struct SAggSupporter *pSup, struct SOptrBasicInfo *pInfo, char **result, int32_t *length);
+typedef bool (*__optr_decode_fn_t)(struct SOperatorInfo* pOperator, struct SAggSupporter *pSup, struct SOptrBasicInfo *pInfo, char *result, int32_t length);
 
 typedef int32_t (*__optr_open_fn_t)(struct SOperatorInfo* pOptr);
 typedef SSDataBlock* (*__optr_fn_t)(struct SOperatorInfo* pOptr, bool* newgroup);
@@ -753,6 +755,9 @@ void    setTaskStatus(SExecTaskInfo* pTaskInfo, int8_t status);
 int32_t createExecTaskInfoImpl(SSubplan* pPlan, SExecTaskInfo** pTaskInfo, SReadHandle* pHandle, uint64_t taskId, EOPTR_EXEC_MODEL model);
 int32_t getOperatorExplainExecInfo(SOperatorInfo *operatorInfo, SExplainExecInfo **pRes, int32_t *capacity, int32_t *resNum);
 
+bool aggDecodeResultRow(SOperatorInfo* pOperator, SAggSupporter *pSup, SOptrBasicInfo *pInfo, char* result, int32_t length);
+void aggEncodeResultRow(SOperatorInfo* pOperator, SAggSupporter *pSup, SOptrBasicInfo *pInfo, char **result, int32_t *length);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/libs/executor/src/executorimpl.c b/source/libs/executor/src/executorimpl.c
index e4199a6e29..b86d75cc7b 100644
--- a/source/libs/executor/src/executorimpl.c
+++ b/source/libs/executor/src/executorimpl.c
@@ -300,10 +300,6 @@ SSDataBlock* createOutputBuf_rv1(SDataBlockDescNode* pNode) {
     }
 
     taosArrayPush(pBlock->pDataBlock, &idata);
-
-    if (IS_VAR_DATA_TYPE(idata.info.type)) {
-      pBlock->info.hasVarCol = true;
-    }
   }
 
   return pBlock;
@@ -363,7 +359,7 @@ static void prepareResultListBuffer(SResultRowInfo* pResultRowInfo, jmp_buf env)
   pResultRowInfo->pPosition = taosMemoryRealloc(pResultRowInfo->pPosition, newCapacity * sizeof(SResultRowPosition));
 
   int32_t inc = (int32_t)newCapacity - pResultRowInfo->capacity;
-  memset(&pResultRowInfo->pPosition[pResultRowInfo->capacity], 0, sizeof(SResultRowPosition));
+  memset(&pResultRowInfo->pPosition[pResultRowInfo->capacity], 0, sizeof(SResultRowPosition) * inc);
   pResultRowInfo->capacity = (int32_t)newCapacity;
 }
 
@@ -419,7 +415,7 @@ SResultRow* getNewResultRow_rv(SDiskbasedBuf* pResultBuf, int64_t tableGroupId,
     pData = getBufPage(pResultBuf, getPageId(pi));
     pageId = getPageId(pi);
 
-    if (pData->num + interBufSize + sizeof(SResultRow) > getBufPageSize(pResultBuf)) {
+    if (pData->num + interBufSize > getBufPageSize(pResultBuf)) {
       // release current page first, and prepare the next one
       releaseBufPageInfo(pResultBuf, pi);
 
@@ -439,7 +435,7 @@ SResultRow* getNewResultRow_rv(SDiskbasedBuf* pResultBuf, int64_t tableGroupId,
   pResultRow->pageId = pageId;
   pResultRow->offset = (int32_t)pData->num;
 
-  pData->num += interBufSize + sizeof(SResultRow);
+  pData->num += interBufSize;
 
   return pResultRow;
 }
@@ -507,7 +503,7 @@ static SResultRow* doSetResultOutBufByKey_rv(SDiskbasedBuf* pResultBuf, SResultR
 
       // add a new result set for a new group
       SResultRowPosition pos = {.pageId = pResult->pageId, .offset = pResult->offset};
-      taosHashPut(pSup->pResultRowHashTable, pSup->keyBuf, GET_RES_WINDOW_KEY_LEN(bytes), &pos, POINTER_BYTES);
+      taosHashPut(pSup->pResultRowHashTable, pSup->keyBuf, GET_RES_WINDOW_KEY_LEN(bytes), &pos, sizeof(SResultRowPosition));
       SResultRowCell cell = {.groupId = tableGroupId, .pos = pos};
       taosArrayPush(pSup->pResultRowArrayList, &cell);
     } else {
@@ -4979,6 +4975,21 @@ static int32_t doOpenAggregateOptr(SOperatorInfo* pOperator) {
     // the pDataBlock are always the same one, no need to call this again
     setInputDataBlock(pOperator, pInfo->pCtx, pBlock, order);
     doAggregateImpl(pOperator, 0, pInfo->pCtx);
+
+#if 0   // test for encode/decode result info
+    if(pOperator->encodeResultRow){
+      char *result = NULL;
+      int32_t length = 0;
+      SAggSupporter   *pSup = &pAggInfo->aggSup;
+      pOperator->encodeResultRow(pOperator, pSup, pInfo, &result, &length);
+      taosHashClear(pSup->pResultRowHashTable);
+      pInfo->resultRowInfo.size = 0;
+      pOperator->decodeResultRow(pOperator, pSup, pInfo, result, length);
+      if(result){
+        taosMemoryFree(result);
+      }
+    }
+#endif
   }
 
   finalizeQueryResult(pInfo->pCtx, pOperator->numOfOutput);
@@ -5007,24 +5018,33 @@ static SSDataBlock* getAggregateResult(SOperatorInfo* pOperator, bool* newgroup)
   return (blockDataGetNumOfRows(pInfo->pRes) != 0) ? pInfo->pRes : NULL;
 }
 
-static void aggEncodeResultRow(SOperatorInfo* pOperator, char** result, int32_t* length) {
-  SAggOperatorInfo* pAggInfo = pOperator->info;
-  SAggSupporter*    pSup = &pAggInfo->aggSup;
-
+void aggEncodeResultRow(SOperatorInfo* pOperator, SAggSupporter *pSup, SOptrBasicInfo *pInfo, char **result, int32_t *length) {
   int32_t size = taosHashGetSize(pSup->pResultRowHashTable);
-  size_t  keyLen = POINTER_BYTES;  // estimate the key length
+  size_t  keyLen = sizeof(uint64_t) * 2;  // estimate the key length
   int32_t totalSize = sizeof(int32_t) + size * (sizeof(int32_t) + keyLen + sizeof(int32_t) + pSup->resultRowSize);
   *result = taosMemoryCalloc(1, totalSize);
   if (*result == NULL) {
-    terrno = TSDB_CODE_OUT_OF_MEMORY;
-    return;
+    longjmp(pOperator->pTaskInfo->env, TSDB_CODE_OUT_OF_MEMORY);
   }
   *(int32_t*)(*result) = size;
   int32_t offset = sizeof(int32_t);
+
+  // prepare memory
+  SResultRowPosition* pos = &pInfo->resultRowInfo.pPosition[pInfo->resultRowInfo.curPos];
+  void* pPage = getBufPage(pSup->pResultBuf, pos->pageId);
+  SResultRow* pRow = (SResultRow*)((char*)pPage + pos->offset);
+  setBufPageDirty(pPage, true);
+  releaseBufPage(pSup->pResultBuf, pPage);
+
   void*   pIter = taosHashIterate(pSup->pResultRowHashTable, NULL);
   while (pIter) {
     void*        key = taosHashGetKey(pIter, &keyLen);
-    SResultRow** p1 = (SResultRow**)pIter;
+    SResultRowPosition* p1 = (SResultRowPosition*)pIter;
+
+    pPage = (SFilePage*) getBufPage(pSup->pResultBuf, p1->pageId);
+    pRow = (SResultRow*)((char*)pPage + p1->offset);
+    setBufPageDirty(pPage, true);
+    releaseBufPage(pSup->pResultBuf, pPage);
 
     // recalculate the result size
     int32_t realTotalSize = offset + sizeof(int32_t) + keyLen + sizeof(int32_t) + pSup->resultRowSize;
@@ -5034,7 +5054,7 @@ static void aggEncodeResultRow(SOperatorInfo* pOperator, char** result, int32_t*
         terrno = TSDB_CODE_OUT_OF_MEMORY;
         taosMemoryFree(*result);
         *result = NULL;
-        return;
+        longjmp(pOperator->pTaskInfo->env, TSDB_CODE_OUT_OF_MEMORY);
       } else {
         *result = tmp;
       }
@@ -5048,7 +5068,7 @@ static void aggEncodeResultRow(SOperatorInfo* pOperator, char** result, int32_t*
     // save value
     *(int32_t*)(*result + offset) = pSup->resultRowSize;
     offset += sizeof(int32_t);
-    memcpy(*result + offset, *p1, pSup->resultRowSize);
+    memcpy(*result + offset, pRow, pSup->resultRowSize);
     offset += pSup->resultRowSize;
 
     pIter = taosHashIterate(pSup->pResultRowHashTable, pIter);
@@ -5060,15 +5080,11 @@ static void aggEncodeResultRow(SOperatorInfo* pOperator, char** result, int32_t*
   return;
 }
 
-static bool aggDecodeResultRow(SOperatorInfo* pOperator, char* result, int32_t length) {
+bool aggDecodeResultRow(SOperatorInfo* pOperator, SAggSupporter *pSup, SOptrBasicInfo *pInfo, char* result, int32_t length) {
   if (!result || length <= 0) {
     return false;
   }
 
-  SAggOperatorInfo* pAggInfo = pOperator->info;
-  SAggSupporter*    pSup = &pAggInfo->aggSup;
-  SOptrBasicInfo*   pInfo = &pAggInfo->binfo;
-
   //  int32_t size = taosHashGetSize(pSup->pResultRowHashTable);
   int32_t count = *(int32_t*)(result);
 
@@ -5080,17 +5096,16 @@ static bool aggDecodeResultRow(SOperatorInfo* pOperator, char* result, int32_t l
     uint64_t    tableGroupId = *(uint64_t*)(result + offset);
     SResultRow* resultRow = getNewResultRow_rv(pSup->pResultBuf, tableGroupId, pSup->resultRowSize);
     if (!resultRow) {
-      terrno = TSDB_CODE_TSC_INVALID_INPUT;
-      return false;
+      longjmp(pOperator->pTaskInfo->env, TSDB_CODE_TSC_INVALID_INPUT);
     }
     // add a new result set for a new group
-    taosHashPut(pSup->pResultRowHashTable, result + offset, keyLen, &resultRow, POINTER_BYTES);
+    SResultRowPosition pos = {.pageId = resultRow->pageId, .offset = resultRow->offset};
+    taosHashPut(pSup->pResultRowHashTable, result + offset, keyLen, &pos, sizeof(SResultRowPosition));
 
     offset += keyLen;
     int32_t valueLen = *(int32_t*)(result + offset);
     if (valueLen != pSup->resultRowSize) {
-      terrno = TSDB_CODE_TSC_INVALID_INPUT;
-      return false;
+      longjmp(pOperator->pTaskInfo->env, TSDB_CODE_TSC_INVALID_INPUT);
     }
     offset += sizeof(int32_t);
     int32_t pageId = resultRow->pageId;
@@ -5101,13 +5116,13 @@ static bool aggDecodeResultRow(SOperatorInfo* pOperator, char* result, int32_t l
     offset += valueLen;
 
     initResultRow(resultRow);
-    pInfo->resultRowInfo.pPosition[pInfo->resultRowInfo.size++] =
-        (SResultRowPosition){.pageId = resultRow->pageId, .offset = resultRow->offset};
+    prepareResultListBuffer(&pInfo->resultRowInfo, pOperator->pTaskInfo->env);
+    pInfo->resultRowInfo.curPos = pInfo->resultRowInfo.size;
+    pInfo->resultRowInfo.pPosition[pInfo->resultRowInfo.size++] = (SResultRowPosition) {.pageId = resultRow->pageId, .offset = resultRow->offset};
   }
 
   if (offset != length) {
-    terrno = TSDB_CODE_TSC_INVALID_INPUT;
-    return false;
+    longjmp(pOperator->pTaskInfo->env, TSDB_CODE_TSC_INVALID_INPUT);
   }
   return true;
 }
@@ -5333,6 +5348,21 @@ static int32_t doOpenIntervalAgg(SOperatorInfo* pOperator) {
     // the pDataBlock are always the same one, no need to call this again
     setInputDataBlock(pOperator, pInfo->binfo.pCtx, pBlock, order);
     hashIntervalAgg(pOperator, &pInfo->binfo.resultRowInfo, pBlock, 0);
+
+#if 0   // test for encode/decode result info
+    if(pOperator->encodeResultRow){
+      char *result = NULL;
+      int32_t length = 0;
+      SAggSupporter   *pSup = &pInfo->aggSup;
+      pOperator->encodeResultRow(pOperator, pSup, &pInfo->binfo, &result, &length);
+      taosHashClear(pSup->pResultRowHashTable);
+      pInfo->binfo.resultRowInfo.size = 0;
+      pOperator->decodeResultRow(pOperator, pSup, &pInfo->binfo, result, length);
+      if(result){
+        taosMemoryFree(result);
+      }
+    }
+#endif
   }
 
   closeAllResultRows(&pInfo->binfo.resultRowInfo);
@@ -5752,7 +5782,6 @@ static SSDataBlock* doSessionWindowAgg(SOperatorInfo* pOperator, bool* newgroup)
   return pBInfo->pRes->info.rows == 0 ? NULL : pBInfo->pRes;
 }
 
-
 static void doHandleRemainBlockForNewGroupImpl(SFillOperatorInfo* pInfo, SResultInfo* pResultInfo, bool* newgroup,
                                                SExecTaskInfo* pTaskInfo) {
   pInfo->totalInputRows = pInfo->existNewGroupBlock->info.rows;
@@ -6218,6 +6247,8 @@ SOperatorInfo* createIntervalOperatorInfo(SOperatorInfo* downstream, SExprInfo*
   pOperator->getNextFn    = doBuildIntervalResult;
   pOperator->getStreamResFn= doStreamIntervalAgg;
   pOperator->closeFn      = destroyIntervalOperatorInfo;
+  pOperator->encodeResultRow = aggEncodeResultRow;
+  pOperator->decodeResultRow = aggDecodeResultRow;
 
   code = appendDownstream(pOperator, &downstream, 1);
   if (code != TSDB_CODE_SUCCESS) {
@@ -6287,6 +6318,8 @@ SOperatorInfo* createStatewindowOperatorInfo(SOperatorInfo* downstream, SExprInf
   pOperator->info         = pInfo;
   pOperator->getNextFn    = doStateWindowAgg;
   pOperator->closeFn      = destroyStateWindowOperatorInfo;
+  pOperator->encodeResultRow = aggEncodeResultRow;
+  pOperator->decodeResultRow = aggDecodeResultRow;
 
   int32_t code = appendDownstream(pOperator, &downstream, 1);
   return pOperator;
@@ -6327,6 +6360,8 @@ SOperatorInfo* createSessionAggOperatorInfo(SOperatorInfo* downstream, SExprInfo
   pOperator->info         = pInfo;
   pOperator->getNextFn    = doSessionWindowAgg;
   pOperator->closeFn      = destroySWindowOperatorInfo;
+  pOperator->encodeResultRow = aggEncodeResultRow;
+  pOperator->decodeResultRow = aggDecodeResultRow;
   pOperator->pTaskInfo    = pTaskInfo;
 
   code = appendDownstream(pOperator, &downstream, 1);
@@ -6379,6 +6414,7 @@ SOperatorInfo* createAllMultiTableTimeIntervalOperatorInfo(STaskRuntimeEnv* pRun
   pOperator->name = "AllMultiTableTimeIntervalOperator";
   //  pOperator->operatorType = OP_AllMultiTableTimeInterval;
   pOperator->blockingOptr = true;
+
   pOperator->status = OP_NOT_OPENED;
   pOperator->pExpr = pExpr;
   pOperator->numOfOutput = numOfOutput;
diff --git a/source/libs/executor/src/groupoperator.c b/source/libs/executor/src/groupoperator.c
index 9410d1384d..8a10170fcd 100644
--- a/source/libs/executor/src/groupoperator.c
+++ b/source/libs/executor/src/groupoperator.c
@@ -166,7 +166,7 @@ static int32_t buildGroupKeys(void* pKey, const SArray* pGroupColVals) {
 // assign the group keys or user input constant values if required
 static void doAssignGroupKeys(SqlFunctionCtx* pCtx, int32_t numOfOutput, int32_t totalRows, int32_t rowIndex) {
   for (int32_t i = 0; i < numOfOutput; ++i) {
-    if (pCtx[i].functionId == -1) {
+    if (pCtx[i].functionId == -1) {       // select count(*),key from t group by key.
       SResultRowEntryInfo* pEntryInfo = GET_RES_INFO(&pCtx[i]);
 
       SColumnInfoData* pColInfoData = pCtx[i].input.pData[0];
@@ -344,7 +344,7 @@ SOperatorInfo* createGroupOperatorInfo(SOperatorInfo* downstream, SExprInfo* pEx
   pOperator->name         = "GroupbyAggOperator";
   pOperator->blockingOptr = true;
   pOperator->status       = OP_NOT_OPENED;
-  //  pOperator->operatorType = OP_Groupby;
+  // pOperator->operatorType = OP_Groupby;
   pOperator->pExpr        = pExprInfo;
   pOperator->numOfOutput  = numOfCols;
   pOperator->info         = pInfo;
@@ -352,6 +352,8 @@ SOperatorInfo* createGroupOperatorInfo(SOperatorInfo* downstream, SExprInfo* pEx
   pOperator->_openFn      = operatorDummyOpenFn;
   pOperator->getNextFn    = hashGroupbyAggregate;
   pOperator->closeFn      = destroyGroupOperatorInfo;
+  pOperator->encodeResultRow = aggEncodeResultRow;
+  pOperator->decodeResultRow = aggDecodeResultRow;
 
   code = appendDownstream(pOperator, &downstream, 1);
   return pOperator;
diff --git a/source/libs/scalar/src/filter.c b/source/libs/scalar/src/filter.c
index 2e47e19023..191143de12 100644
--- a/source/libs/scalar/src/filter.c
+++ b/source/libs/scalar/src/filter.c
@@ -1748,7 +1748,6 @@ int32_t fltInitValFieldData(SFilterInfo *info) {
     SFilterField* fi = right;
     
     SValueNode* var = (SValueNode *)fi->desc;
-
     if (var == NULL) {
       assert(fi->data != NULL);
       continue;
@@ -1767,13 +1766,18 @@ int32_t fltInitValFieldData(SFilterInfo *info) {
     }
 
     SDataType *dType = &var->node.resType;
+    size_t bytes = 0;
 
     if (type == TSDB_DATA_TYPE_BINARY) {
       size_t len = (dType->type == TSDB_DATA_TYPE_BINARY || dType->type == TSDB_DATA_TYPE_NCHAR) ? dType->bytes : MAX_NUM_STR_SIZE;
-      fi->data = taosMemoryCalloc(1, len + 1 + VARSTR_HEADER_SIZE);
+      bytes = len + 1 + VARSTR_HEADER_SIZE;
+
+      fi->data = taosMemoryCalloc(1, bytes);
     } else if (type == TSDB_DATA_TYPE_NCHAR) {
-      size_t len = (dType->type == TSDB_DATA_TYPE_BINARY || dType->type == TSDB_DATA_TYPE_NCHAR) ? dType->bytes : MAX_NUM_STR_SIZE;    
-      fi->data = taosMemoryCalloc(1, (len + 1) * TSDB_NCHAR_SIZE + VARSTR_HEADER_SIZE);
+      size_t len = (dType->type == TSDB_DATA_TYPE_BINARY || dType->type == TSDB_DATA_TYPE_NCHAR) ? dType->bytes : MAX_NUM_STR_SIZE;
+      bytes = (len + 1) * TSDB_NCHAR_SIZE + VARSTR_HEADER_SIZE;
+
+      fi->data = taosMemoryCalloc(1, bytes);
     } else if (type != TSDB_DATA_TYPE_JSON){
       if (dType->type == TSDB_DATA_TYPE_VALUE_ARRAY) {  //TIME RANGE
 /*      
@@ -1797,8 +1801,11 @@ int32_t fltInitValFieldData(SFilterInfo *info) {
       } else {
         SScalarParam out = {.columnData = taosMemoryCalloc(1, sizeof(SColumnInfoData))};
         out.columnData->info.type = type;
-        out.columnData->info.bytes = tDataTypes[type].bytes;
-        ASSERT(!IS_VAR_DATA_TYPE(type));
+        if (IS_VAR_DATA_TYPE(type)) {
+          out.columnData->info.bytes = bytes;
+        } else {
+          out.columnData->info.bytes = tDataTypes[type].bytes;
+        }
 
         // todo refactor the convert
         int32_t code = doConvertDataType(var, &out);
@@ -2985,13 +2992,13 @@ bool filterExecuteImplMisc(void *pinfo, int32_t numOfRows, int8_t** p, SColumnDa
   for (int32_t i = 0; i < numOfRows; ++i) {
     uint32_t uidx = info->groups[0].unitIdxs[0];
     void *colData = colDataGetData((SColumnInfoData *)info->cunits[uidx].colData, i);
-    if (colData == NULL || colDataIsNull((SColumnInfoData *)info->cunits[uidx].colData, 0, i, NULL)) {
+    if (colData == NULL || colDataIsNull_s((SColumnInfoData *)info->cunits[uidx].colData, i)) {
       (*p)[i] = 0;
       all = false;
       continue;
     }
-    // match/nmatch for nchar type need convert from ucs4 to mbs
 
+    // match/nmatch for nchar type need convert from ucs4 to mbs
     if(info->cunits[uidx].dataType == TSDB_DATA_TYPE_NCHAR && (info->cunits[uidx].optr == OP_TYPE_MATCH || info->cunits[uidx].optr == OP_TYPE_NMATCH)){
       char *newColData = taosMemoryCalloc(info->cunits[uidx].dataSize * TSDB_NCHAR_SIZE + VARSTR_HEADER_SIZE, 1);
       int32_t len = taosUcs4ToMbs((TdUcs4*)varDataVal(colData), varDataLen(colData), varDataVal(newColData));
@@ -3222,19 +3229,13 @@ int32_t fltInitFromNode(SNode* tree, SFilterInfo *info, uint32_t options) {
   info->unitFlags = taosMemoryMalloc(info->unitNum * sizeof(*info->unitFlags));
 
   filterDumpInfoToString(info, "Final", 0);
-
   return code;
 
 _return:
-
   qInfo("init from node failed, code:%d", code);
-  
   return code;
 }
 
-
-
-
 bool filterRangeExecute(SFilterInfo *info, SColumnDataAgg *pDataStatis, int32_t numOfCols, int32_t numOfRows) {
   if (FILTER_EMPTY_RES(info)) {
     return false;
diff --git a/source/libs/scalar/src/scalar.c b/source/libs/scalar/src/scalar.c
index f97e5a2d2a..116dfdd5d5 100644
--- a/source/libs/scalar/src/scalar.c
+++ b/source/libs/scalar/src/scalar.c
@@ -46,7 +46,6 @@ int32_t doConvertDataType(SValueNode* pValueNode, SScalarParam* out) {
   colDataAppend(in.columnData, 0, nodesGetValueFromNode(pValueNode), false);
 
   colInfoDataEnsureCapacity(out->columnData, 1);
-
   int32_t code = vectorConvertImpl(&in, out);
   sclFreeParam(&in);
 
diff --git a/source/libs/scalar/src/sclvector.c b/source/libs/scalar/src/sclvector.c
index 4bce8f33f2..05456790a5 100644
--- a/source/libs/scalar/src/sclvector.c
+++ b/source/libs/scalar/src/sclvector.c
@@ -177,9 +177,24 @@ static FORCE_INLINE void varToBool(char *buf, SScalarParam* pOut, int32_t rowInd
   colDataAppendInt8(pOut->columnData, rowIndex, (int8_t*) &v);
 }
 
+static FORCE_INLINE void varToNchar(char* buf, SScalarParam* pOut, int32_t rowIndex) {
+  int32_t len = 0;
+  int32_t inputLen = varDataLen(buf);
+
+  char* t = taosMemoryCalloc(1,(inputLen + 1) * TSDB_NCHAR_SIZE + VARSTR_HEADER_SIZE);
+  /*int32_t resLen = */taosMbsToUcs4(varDataVal(buf), inputLen, (TdUcs4*) varDataVal(t), pOut->columnData->info.bytes, &len);
+  varDataSetLen(t, len);
+
+  colDataAppend(pOut->columnData, rowIndex, t, false);
+  taosMemoryFree(t);
+}
+
+//TODO opt performance, tmp is not needed.
 int32_t vectorConvertFromVarData(const SScalarParam* pIn, SScalarParam* pOut, int32_t inType, int32_t outType) {
   int32_t bufSize = pIn->columnData->info.bytes;
-  char *tmp = taosMemoryMalloc(bufSize);
+  char *tmp = taosMemoryMalloc(bufSize + VARSTR_HEADER_SIZE);
+
+  bool vton = false;
 
   _bufConverteFunc func = NULL;
   if (TSDB_DATA_TYPE_BOOL == outType) {
@@ -190,6 +205,9 @@ int32_t vectorConvertFromVarData(const SScalarParam* pIn, SScalarParam* pOut, in
     func = varToUnsigned;
   } else if (IS_FLOAT_TYPE(outType)) {
     func = varToFloat;
+  } else if (outType == TSDB_DATA_TYPE_NCHAR) {
+    func = varToNchar;
+    vton = true;
   } else {
     sclError("invalid convert outType:%d", outType);
     return TSDB_CODE_QRY_APP_ERROR;
@@ -197,26 +215,30 @@ int32_t vectorConvertFromVarData(const SScalarParam* pIn, SScalarParam* pOut, in
 
   pOut->numOfRows = pIn->numOfRows;
   for (int32_t i = 0; i < pIn->numOfRows; ++i) {
-    if (colDataIsNull(pIn->columnData, pIn->numOfRows, i, NULL)) {
+    if (colDataIsNull_s(pIn->columnData, i)) {
       colDataAppendNULL(pOut->columnData, i);
       continue;
     }
 
     char* data = colDataGetData(pIn->columnData, i);
-    if (TSDB_DATA_TYPE_BINARY == inType) {
-      memcpy(tmp, varDataVal(data), varDataLen(data));
-      tmp[varDataLen(data)] = 0;
+    if (vton) {
+      memcpy(tmp, data, varDataTLen(data));
     } else {
-      ASSERT (varDataLen(data) <= bufSize);
-      
-      int len = taosUcs4ToMbs((TdUcs4*)varDataVal(data), varDataLen(data), tmp);
-      if (len < 0){
-        sclError("castConvert taosUcs4ToMbs error 1");
-        taosMemoryFreeClear(tmp);
-        return TSDB_CODE_QRY_APP_ERROR;
+      if (TSDB_DATA_TYPE_VARCHAR == inType) {
+        memcpy(tmp, varDataVal(data), varDataLen(data));
+        tmp[varDataLen(data)] = 0;
+      } else {
+        ASSERT(varDataLen(data) <= bufSize);
+
+        int len = taosUcs4ToMbs((TdUcs4 *)varDataVal(data), varDataLen(data), tmp);
+        if (len < 0) {
+          sclError("castConvert taosUcs4ToMbs error 1");
+          taosMemoryFreeClear(tmp);
+          return TSDB_CODE_QRY_APP_ERROR;
+        }
+
+        tmp[len] = 0;
       }
-      
-      tmp[len] = 0;
     }
     
     (*func)(tmp, pOut, i);