diff --git a/source/dnode/vnode/src/tsdb/tsdbRead.c b/source/dnode/vnode/src/tsdb/tsdbRead.c
index 51f7f237762b8900c61c9c5d1e7bf42b4a52a9c5..5f796bbab95ada51b263af84d0c49e919dc0f0a0 100644
--- a/source/dnode/vnode/src/tsdb/tsdbRead.c
+++ b/source/dnode/vnode/src/tsdb/tsdbRead.c
@@ -323,6 +323,9 @@ static bool filesetIteratorNext(SFilesetIter* pIter, STsdbReader* pReader) {
 
     if ((asc && (win.ekey < pReader->window.skey)) || ((!asc) && (win.skey > pReader->window.ekey))) {
       pIter->index += step;
+      if ((asc && pIter->index >= pIter->numOfFiles) || ((!asc) && pIter->index < 0)) {
+        return false;
+      }
       continue;
     }
 
diff --git a/source/libs/executor/inc/executorimpl.h b/source/libs/executor/inc/executorimpl.h
index 7cba2c9eaf2f148f008665b31ffbbf77ec8c1238..1a27daed4c457eeec33e7af5310f9719d85e91bb 100644
--- a/source/libs/executor/inc/executorimpl.h
+++ b/source/libs/executor/inc/executorimpl.h
@@ -529,6 +529,9 @@ typedef struct SIndefOperatorInfo {
   SArray*            pPseudoColInfo;
   SExprSupp          scalarSup;
   SNode*             pCondition;
+  uint64_t           groupId;
+
+  SSDataBlock*       pNextGroupRes;
 } SIndefOperatorInfo;
 
 typedef struct SFillOperatorInfo {
diff --git a/source/libs/executor/src/executorimpl.c b/source/libs/executor/src/executorimpl.c
index cd6b2a83d1ef9bed89202520afdff35eceab1c52..609afff884a991c1eab7b0422ce287a1dcc99110 100644
--- a/source/libs/executor/src/executorimpl.c
+++ b/source/libs/executor/src/executorimpl.c
@@ -571,8 +571,8 @@ int32_t projectApplyFunctions(SExprInfo* pExpr, SSDataBlock* pResult, SSDataBloc
   setPseudoOutputColInfo(pResult, pCtx, pPseudoList);
   pResult->info.groupId = pSrcBlock->info.groupId;
 
-  // if the source equals to the destination, it is to create a new column as the result of scalar function or some
-  // operators.
+  // if the source equals to the destination, it is to create a new column as the result of scalar
+  // function or some operators.
   bool createNewColModel = (pResult == pSrcBlock);
 
   int32_t numOfRows = 0;
@@ -580,17 +580,17 @@ int32_t projectApplyFunctions(SExprInfo* pExpr, SSDataBlock* pResult, SSDataBloc
   for (int32_t k = 0; k < numOfOutput; ++k) {
     int32_t         outputSlotId = pExpr[k].base.resSchema.slotId;
     SqlFunctionCtx* pfCtx = &pCtx[k];
+    SInputColumnInfoData* pInputData = &pfCtx->input;
 
     if (pExpr[k].pExpr->nodeType == QUERY_NODE_COLUMN) {  // it is a project query
       SColumnInfoData* pColInfoData = taosArrayGet(pResult->pDataBlock, outputSlotId);
       if (pResult->info.rows > 0 && !createNewColModel) {
-        colDataMergeCol(pColInfoData, pResult->info.rows, &pResult->info.capacity, pfCtx->input.pData[0],
-                        pfCtx->input.numOfRows);
+        colDataMergeCol(pColInfoData, pResult->info.rows, &pResult->info.capacity, pInputData->pData[0], pInputData->numOfRows);
       } else {
-        colDataAssign(pColInfoData, pfCtx->input.pData[0], pfCtx->input.numOfRows, &pResult->info);
+        colDataAssign(pColInfoData, pInputData->pData[0], pInputData->numOfRows, &pResult->info);
       }
 
-      numOfRows = pfCtx->input.numOfRows;
+      numOfRows = pInputData->numOfRows;
     } else if (pExpr[k].pExpr->nodeType == QUERY_NODE_VALUE) {
       SColumnInfoData* pColInfoData = taosArrayGet(pResult->pDataBlock, outputSlotId);
 
@@ -623,14 +623,12 @@ int32_t projectApplyFunctions(SExprInfo* pExpr, SSDataBlock* pResult, SSDataBloc
       numOfRows = dest.numOfRows;
       taosArrayDestroy(pBlockList);
     } else if (pExpr[k].pExpr->nodeType == QUERY_NODE_FUNCTION) {
-      ASSERT(!fmIsAggFunc(pfCtx->functionId));
-
       // _rowts/_c0, not tbname column
       if (fmIsPseudoColumnFunc(pfCtx->functionId) && (!fmIsScanPseudoColumnFunc(pfCtx->functionId))) {
         // do nothing
       } else if (fmIsIndefiniteRowsFunc(pfCtx->functionId)) {
-        SResultRowEntryInfo* pResInfo = GET_RES_INFO(&pCtx[k]);
-        pfCtx->fpSet.init(&pCtx[k], pResInfo);
+        SResultRowEntryInfo* pResInfo = GET_RES_INFO(pfCtx);
+        pfCtx->fpSet.init(pfCtx, pResInfo);
 
         pfCtx->pOutput = taosArrayGet(pResult->pDataBlock, outputSlotId);
         pfCtx->offset = createNewColModel ? 0 : pResult->info.rows;  // set the start offset
@@ -642,6 +640,23 @@ int32_t projectApplyFunctions(SExprInfo* pExpr, SSDataBlock* pResult, SSDataBloc
         }
 
         numOfRows = pfCtx->fpSet.process(pfCtx);
+      } else if (fmIsAggFunc(fmIsAggFunc(pfCtx->functionId))) {
+        // _group_key function for "partition by tbname" + csum(col_name) query
+        SColumnInfoData* pOutput = taosArrayGet(pResult->pDataBlock, outputSlotId);
+        int32_t slotId = pfCtx->param[0].pCol->slotId;
+
+        // todo handle the json tag
+        SColumnInfoData* pInput = taosArrayGet(pSrcBlock->pDataBlock, slotId);
+        for(int32_t f = 0; f < pSrcBlock->info.rows; ++f) {
+          bool isNull = colDataIsNull_s(pInput, f);
+          if (isNull) {
+            colDataAppendNULL(pOutput, pResult->info.rows + f);
+          } else {
+            char* data = colDataGetData(pInput, f);
+            colDataAppend(pOutput, pResult->info.rows + f, data, isNull);
+          }
+        }
+
       } else {
         SArray* pBlockList = taosArrayInit(4, POINTER_BYTES);
         taosArrayPush(pBlockList, &pSrcBlock);
@@ -675,25 +690,6 @@ int32_t projectApplyFunctions(SExprInfo* pExpr, SSDataBlock* pResult, SSDataBloc
   return TSDB_CODE_SUCCESS;
 }
 
-static void setResultRowKey(SResultRow* pResultRow, char* pData, int16_t type) {
-  if (IS_VAR_DATA_TYPE(type)) {
-    // todo disable this
-
-    //    if (pResultRow->key == NULL) {
-    //      pResultRow->key = taosMemoryMalloc(varDataTLen(pData));
-    //      varDataCopy(pResultRow->key, pData);
-    //    } else {
-    //      ASSERT(memcmp(pResultRow->key, pData, varDataTLen(pData)) == 0);
-    //    }
-  } else {
-    int64_t v = -1;
-    GET_TYPED_DATA(v, int64_t, type, pData);
-
-    pResultRow->win.skey = v;
-    pResultRow->win.ekey = v;
-  }
-}
-
 bool functionNeedToExecute(SqlFunctionCtx* pCtx) {
   struct SResultRowEntryInfo* pResInfo = GET_RES_INFO(pCtx);
 
@@ -3825,6 +3821,40 @@ _error:
   return NULL;
 }
 
+static void doHandleDataBlock(SOperatorInfo* pOperator, SSDataBlock* pBlock, SOperatorInfo* downstream, SExecTaskInfo* pTaskInfo) {
+  int32_t order = 0;
+  int32_t scanFlag = 0;
+
+  SIndefOperatorInfo* pIndefInfo = pOperator->info;
+  SOptrBasicInfo*     pInfo = &pIndefInfo->binfo;
+  SExprSupp*          pSup = &pOperator->exprSupp;
+
+  // the pDataBlock are always the same one, no need to call this again
+  int32_t code = getTableScanInfo(downstream, &order, &scanFlag);
+  if (code != TSDB_CODE_SUCCESS) {
+    longjmp(pTaskInfo->env, code);
+  }
+
+  // there is an scalar expression that needs to be calculated before apply the group aggregation.
+  SExprSupp* pScalarSup = &pIndefInfo->scalarSup;
+  if (pScalarSup->pExprInfo != NULL) {
+    code = projectApplyFunctions(pScalarSup->pExprInfo, pBlock, pBlock, pScalarSup->pCtx, pScalarSup->numOfExprs,
+                                 pIndefInfo->pPseudoColInfo);
+    if (code != TSDB_CODE_SUCCESS) {
+      longjmp(pTaskInfo->env, code);
+    }
+  }
+
+  setInputDataBlock(pOperator, pSup->pCtx, pBlock, order, scanFlag, false);
+  blockDataEnsureCapacity(pInfo->pRes, pInfo->pRes->info.rows + pBlock->info.rows);
+
+  code = projectApplyFunctions(pSup->pExprInfo, pInfo->pRes, pBlock, pSup->pCtx, pSup->numOfExprs,
+                               pIndefInfo->pPseudoColInfo);
+  if (code != TSDB_CODE_SUCCESS) {
+    longjmp(pTaskInfo->env, code);
+  }
+}
+
 static SSDataBlock* doApplyIndefinitFunction(SOperatorInfo* pOperator) {
   SIndefOperatorInfo* pIndefInfo = pOperator->info;
   SOptrBasicInfo*     pInfo = &pIndefInfo->binfo;
@@ -3839,8 +3869,6 @@ static SSDataBlock* doApplyIndefinitFunction(SOperatorInfo* pOperator) {
   }
 
   int64_t st = 0;
-  int32_t order = 0;
-  int32_t scanFlag = 0;
 
   if (pOperator->cost.openCost == 0) {
     st = taosGetTimestampUs();
@@ -3848,42 +3876,54 @@ static SSDataBlock* doApplyIndefinitFunction(SOperatorInfo* pOperator) {
 
   SOperatorInfo* downstream = pOperator->pDownstream[0];
 
-  while (1) {
-    // The downstream exec may change the value of the newgroup, so use a local variable instead.
-    SSDataBlock* pBlock = downstream->fpSet.getNextFn(downstream);
-    if (pBlock == NULL) {
-      doSetOperatorCompleted(pOperator);
-      break;
-    }
+  while(1) {
+    // here we need to handle the existsed group results
+    if (pIndefInfo->pNextGroupRes != NULL) { // todo extract method
+      for (int32_t k = 0; k < pSup->numOfExprs; ++k) {
+        SqlFunctionCtx* pCtx = &pSup->pCtx[k];
 
-    // the pDataBlock are always the same one, no need to call this again
-    int32_t code = getTableScanInfo(pOperator->pDownstream[0], &order, &scanFlag);
-    if (code != TSDB_CODE_SUCCESS) {
-      longjmp(pTaskInfo->env, code);
+        SResultRowEntryInfo* pResInfo = GET_RES_INFO(pCtx);
+        pResInfo->initialized = false;
+        pCtx->pOutput = NULL;
+      }
+
+      doHandleDataBlock(pOperator, pIndefInfo->pNextGroupRes, downstream, pTaskInfo);
+      pIndefInfo->pNextGroupRes = NULL;
     }
 
-    // there is an scalar expression that needs to be calculated before apply the group aggregation.
-    SExprSupp* pScalarSup = &pIndefInfo->scalarSup;
-    if (pScalarSup->pExprInfo != NULL) {
-      code = projectApplyFunctions(pScalarSup->pExprInfo, pBlock, pBlock, pScalarSup->pCtx, pScalarSup->numOfExprs,
-                                   pIndefInfo->pPseudoColInfo);
-      if (code != TSDB_CODE_SUCCESS) {
-        longjmp(pTaskInfo->env, code);
+    if (pInfo->pRes->info.rows < pOperator->resultInfo.threshold) {
+      while (1) {
+        // The downstream exec may change the value of the newgroup, so use a local variable instead.
+        SSDataBlock* pBlock = downstream->fpSet.getNextFn(downstream);
+        if (pBlock == NULL) {
+          doSetOperatorCompleted(pOperator);
+          break;
+        }
+
+        if (pIndefInfo->groupId == 0 && pBlock->info.groupId != 0) {
+          pIndefInfo->groupId = pBlock->info.groupId;  // this is the initial group result
+        } else {
+          if (pIndefInfo->groupId != pBlock->info.groupId) {  // reset output buffer and computing status
+            pIndefInfo->groupId = pBlock->info.groupId;
+            pIndefInfo->pNextGroupRes = pBlock;
+            break;
+          }
+        }
+
+        doHandleDataBlock(pOperator, pBlock, downstream, pTaskInfo);
+        if (pInfo->pRes->info.rows >= pOperator->resultInfo.threshold) {
+          break;
+        }
       }
     }
 
-    setInputDataBlock(pOperator, pSup->pCtx, pBlock, order, scanFlag, false);
-    blockDataEnsureCapacity(pInfo->pRes, pInfo->pRes->info.rows + pBlock->info.rows);
-
-    code = projectApplyFunctions(pOperator->exprSupp.pExprInfo, pInfo->pRes, pBlock, pSup->pCtx,
-                                 pOperator->exprSupp.numOfExprs, pIndefInfo->pPseudoColInfo);
-    if (code != TSDB_CODE_SUCCESS) {
-      longjmp(pTaskInfo->env, code);
+    doFilter(pIndefInfo->pCondition, pInfo->pRes);
+    size_t rows = pInfo->pRes->info.rows;
+    if (rows >= 0) {
+      break;
     }
   }
 
-  doFilter(pIndefInfo->pCondition, pInfo->pRes);
-
   size_t rows = pInfo->pRes->info.rows;
   pOperator->resultInfo.totalRows += rows;
 
@@ -3928,24 +3968,23 @@ SOperatorInfo* createIndefinitOutputOperatorInfo(SOperatorInfo* downstream, SPhy
   if (numOfRows * pResBlock->info.rowSize > TWOMB) {
     numOfRows = TWOMB / pResBlock->info.rowSize;
   }
+
   initResultSizeInfo(pOperator, numOfRows);
 
-  initAggInfo(&pOperator->exprSupp, &pInfo->aggSup, pExprInfo, numOfExpr, keyBufSize, pTaskInfo->id.str);
+  initAggInfo(pSup, &pInfo->aggSup, pExprInfo, numOfExpr, keyBufSize, pTaskInfo->id.str);
   initBasicInfo(&pInfo->binfo, pResBlock);
 
   setFunctionResultOutput(pOperator, &pInfo->binfo, &pInfo->aggSup, MAIN_SCAN, numOfExpr);
 
-  pInfo->binfo.pRes = pResBlock;
-  pInfo->pPseudoColInfo = setRowTsColumnOutputInfo(pSup->pCtx, numOfExpr);
-  pInfo->pCondition = pPhyNode->node.pConditions;
+  pInfo->binfo.pRes    = pResBlock;
+  pInfo->pCondition    = pPhyNode->node.pConditions;
+  pInfo->pPseudoColInfo= setRowTsColumnOutputInfo(pSup->pCtx, numOfExpr);
 
-  pOperator->name = "IndefinitOperator";
-  pOperator->operatorType = QUERY_NODE_PHYSICAL_PLAN_PROJECT;
-  pOperator->blocking = false;
-  pOperator->status = OP_NOT_OPENED;
-  pOperator->info = pInfo;
-  pOperator->exprSupp.pExprInfo = pExprInfo;
-  pOperator->exprSupp.numOfExprs = numOfExpr;
+  pOperator->name      = "IndefinitOperator";
+  pOperator->operatorType = QUERY_NODE_PHYSICAL_PLAN_INDEF_ROWS_FUNC;
+  pOperator->blocking  = false;
+  pOperator->status    = OP_NOT_OPENED;
+  pOperator->info      = pInfo;
   pOperator->pTaskInfo = pTaskInfo;
 
   pOperator->fpSet = createOperatorFpSet(operatorDummyOpenFn, doApplyIndefinitFunction, NULL, NULL,