diff --git a/source/libs/executor/src/sortoperator.c b/source/libs/executor/src/sortoperator.c
index 9d13276e6d..1880d169bf 100644
--- a/source/libs/executor/src/sortoperator.c
+++ b/source/libs/executor/src/sortoperator.c
@@ -232,6 +232,260 @@ int32_t getExplainExecInfo(SOperatorInfo* pOptr, void** pOptrExplain, uint32_t*
   return TSDB_CODE_SUCCESS;
 }
 
+//=====================================================================================
+// Group Sort Operator
+typedef enum EChildOperatorStatus {CHILD_OP_NEW_GROUP, CHILD_OP_SAME_GROUP, CHILD_OP_FINISHED} EChildOperatorStatus;
+
+typedef struct SGroupSortOperatorInfo {
+  SOptrBasicInfo binfo;
+  uint32_t     sortBufSize;    // max buffer size for in-memory sort
+  SArray*      pSortInfo;
+  SArray*      pColMatchInfo;  // for index map from table scan output
+  int32_t      bufPageSize;
+
+  int64_t      startTs;       // sort start time
+  uint64_t     sortElapsed;   // sort elapsed time, time to flush to disk not included.
+  SSDataBlock* prefetchedDatablock;
+  bool         hasGroupId;
+  uint64_t     currGroupId;
+  SSortHandle* pCurrSortHandle;
+
+  EChildOperatorStatus childOpStatus;
+} SGroupSortOperatorInfo;
+
+
+SSDataBlock* getGroupSortedBlockData(SSortHandle* pHandle, SSDataBlock* pDataBlock, int32_t capacity, SArray* pColMatchInfo,
+                                     SGroupSortOperatorInfo* pInfo) {
+  blockDataCleanup(pDataBlock);
+
+  SSDataBlock* p = tsortGetSortedDataBlock(pHandle);
+  if (p == NULL) {
+    return NULL;
+  }
+
+  blockDataEnsureCapacity(p, capacity);
+
+  while (1) {
+    STupleHandle* pTupleHandle = tsortNextTuple(pHandle);
+    if (pTupleHandle == NULL) {
+      break;
+    }
+
+    appendOneRowToDataBlock(p, pTupleHandle);
+    if (p->info.rows >= capacity) {
+      break;
+    }
+  }
+
+  if (p->info.rows > 0) {
+    int32_t numOfCols = taosArrayGetSize(pColMatchInfo);
+    for (int32_t i = 0; i < numOfCols; ++i) {
+      SColMatchInfo* pmInfo = taosArrayGet(pColMatchInfo, i);
+      ASSERT(pmInfo->matchType == COL_MATCH_FROM_SLOT_ID);
+
+      SColumnInfoData* pSrc = taosArrayGet(p->pDataBlock, pmInfo->srcSlotId);
+      SColumnInfoData* pDst = taosArrayGet(pDataBlock->pDataBlock, pmInfo->targetSlotId);
+      colDataAssign(pDst, pSrc, p->info.rows);
+    }
+
+    pDataBlock->info.rows = p->info.rows;
+    pDataBlock->info.capacity = p->info.rows;
+  }
+
+  blockDataDestroy(p);
+  return (pDataBlock->info.rows > 0) ? pDataBlock : NULL;
+}
+
+
+typedef struct SGroupSortSourceParam {
+  SOperatorInfo*  childOpInfo;
+  SGroupSortOperatorInfo* grpSortOpInfo;
+} SGroupSortSourceParam;
+
+
+SSDataBlock* fetchNextGroupSortDataBlock(void* param) {
+  SGroupSortSourceParam* source = param;
+  SGroupSortOperatorInfo* grpSortOpInfo = source->grpSortOpInfo;
+  if (grpSortOpInfo->prefetchedDatablock) {
+    SSDataBlock* pBlock = grpSortOpInfo->prefetchedDatablock;
+    grpSortOpInfo->prefetchedDatablock = NULL;
+    return pBlock;
+  } else {
+    SOperatorInfo* childOp = source->childOpInfo;
+    SSDataBlock* block = childOp->fpSet.getNextFn(childOp);
+    if (block != NULL) {
+      if (block->info.groupId == grpSortOpInfo->currGroupId) {
+        grpSortOpInfo->childOpStatus = CHILD_OP_SAME_GROUP;
+        return block;
+      } else {
+        grpSortOpInfo->childOpStatus = CHILD_OP_NEW_GROUP;
+        grpSortOpInfo->prefetchedDatablock = block;
+        return NULL;
+      }
+    } else {
+      grpSortOpInfo->childOpStatus = CHILD_OP_FINISHED;
+      return NULL;
+    }
+  }
+}
+
+
+int32_t beginSortGroup(SOperatorInfo* pOperator) {
+  SGroupSortOperatorInfo* pInfo = pOperator->info;
+  SExecTaskInfo*     pTaskInfo = pOperator->pTaskInfo;
+
+
+  //  pInfo->binfo.pRes is not equalled to the input datablock.
+  pInfo->pCurrSortHandle = tsortCreateSortHandle(pInfo->pSortInfo, SORT_SINGLESOURCE_SORT, -1, -1,
+                                             NULL, pTaskInfo->id.str);
+
+  tsortSetFetchRawDataFp(pInfo->pCurrSortHandle, fetchNextGroupSortDataBlock, applyScalarFunction, pOperator);
+
+  SSortSource* ps = taosMemoryCalloc(1, sizeof(SSortSource));
+  SGroupSortSourceParam* param = taosMemoryCalloc(1, sizeof(SGroupSortSourceParam));
+  param->childOpInfo = pOperator->pDownstream[0];
+  param->grpSortOpInfo = pInfo;
+  ps->param = param;
+  tsortAddSource(pInfo->pCurrSortHandle, ps);
+
+  int32_t code = tsortOpen(pInfo->pCurrSortHandle);
+  taosMemoryFreeClear(ps);
+
+  if (code != TSDB_CODE_SUCCESS) {
+    longjmp(pTaskInfo->env, terrno);
+  }
+
+  return TSDB_CODE_SUCCESS;
+}
+
+int32_t finishSortGroup(SOperatorInfo* pOperator) {
+  SGroupSortOperatorInfo* pInfo = pOperator->info;
+  if (pInfo->pCurrSortHandle != NULL) {
+    tsortDestroySortHandle(pInfo->pCurrSortHandle);
+  }
+  pInfo->pCurrSortHandle = NULL;
+  return TSDB_CODE_SUCCESS;
+
+}
+
+SSDataBlock* doGroupSort(SOperatorInfo* pOperator) {
+  if (pOperator->status == OP_EXEC_DONE) {
+    return NULL;
+  }
+
+  SExecTaskInfo*     pTaskInfo = pOperator->pTaskInfo;
+  SGroupSortOperatorInfo* pInfo = pOperator->info;
+
+  int32_t code = pOperator->fpSet._openFn(pOperator);
+  if (code != TSDB_CODE_SUCCESS) {
+    longjmp(pTaskInfo->env, code);
+  }
+
+  if (!pInfo->hasGroupId) {
+    pInfo->hasGroupId = true;
+
+    pInfo->prefetchedDatablock = pOperator->pDownstream[0]->fpSet.getNextFn(pOperator->pDownstream[0]);
+    pInfo->currGroupId = pInfo->prefetchedDatablock->info.groupId;
+    pInfo->childOpStatus = CHILD_OP_NEW_GROUP;
+    beginSortGroup(pOperator);
+  }
+  SSDataBlock* pBlock = NULL;
+  while (pInfo->childOpStatus != CHILD_OP_FINISHED) {
+    pBlock = getGroupSortedBlockData(pInfo->pCurrSortHandle, pInfo->binfo.pRes, pOperator->resultInfo.capacity,
+                                                  pInfo->pColMatchInfo, pInfo);
+
+    if (pBlock != NULL) {
+      pBlock->info.groupId = pInfo->currGroupId;
+      pOperator->resultInfo.totalRows += pBlock->info.rows;
+    }
+    if (pInfo->childOpStatus == CHILD_OP_NEW_GROUP) {
+      finishSortGroup(pOperator);
+      pInfo->currGroupId = pInfo->prefetchedDatablock->info.groupId;
+      beginSortGroup(pOperator);
+    }
+    return pBlock;
+  }
+
+  if (pInfo->childOpStatus == CHILD_OP_FINISHED) {
+    finishSortGroup(pOperator);
+    doSetOperatorCompleted(pOperator);
+  }
+
+  return pBlock;
+}
+
+int32_t getGroupSortExplainExecInfo(SOperatorInfo* pOptr, void** pOptrExplain, uint32_t* len) {
+  //TODO: accumulate all sort handles;
+  return TSDB_CODE_SUCCESS;
+}
+
+//TODO:
+SOperatorInfo* createGroupSortOperatorInfo(SOperatorInfo* downstream, SSortPhysiNode* pSortPhyNode, SExecTaskInfo* pTaskInfo) {
+  SSortOperatorInfo* pInfo = taosMemoryCalloc(1, sizeof(SSortOperatorInfo));
+  SOperatorInfo*     pOperator = taosMemoryCalloc(1, sizeof(SOperatorInfo));
+  if (pInfo == NULL || pOperator == NULL/* || rowSize > 100 * 1024 * 1024*/) {
+    goto _error;
+  }
+
+  SDataBlockDescNode* pDescNode = pSortPhyNode->node.pOutputDataBlockDesc;
+
+  int32_t      numOfCols = 0;
+  SSDataBlock* pResBlock = createResDataBlock(pDescNode);
+  SExprInfo*   pExprInfo = createExprInfo(pSortPhyNode->pExprs, NULL, &numOfCols);
+
+  int32_t numOfOutputCols = 0;
+  SArray* pColMatchColInfo =
+      extractColMatchInfo(pSortPhyNode->pTargets, pDescNode, &numOfOutputCols, COL_MATCH_FROM_SLOT_ID);
+
+  pOperator->exprSupp.pCtx = createSqlFunctionCtx(pExprInfo, numOfCols, &pOperator->exprSupp.rowEntryInfoOffset);
+  pInfo->binfo.pRes = pResBlock;
+
+  initResultSizeInfo(pOperator, 1024);
+
+  pInfo->pSortInfo        = createSortInfo(pSortPhyNode->pSortKeys);;
+  pInfo->pColMatchInfo    = pColMatchColInfo;
+  pOperator->name         = "GroupSortOperator";
+  //TODO
+  pOperator->operatorType = QUERY_NODE_PHYSICAL_PLAN_SORT;
+  pOperator->blocking     = true;
+  pOperator->status       = OP_NOT_OPENED;
+  pOperator->info         = pInfo;
+  pOperator->exprSupp.pExprInfo        = pExprInfo;
+  pOperator->exprSupp.numOfExprs   = numOfCols;
+  pOperator->pTaskInfo    = pTaskInfo;
+
+  pOperator->fpSet = createOperatorFpSet(operatorDummyOpenFn, doGroupSort, NULL, NULL, destroyOrderOperatorInfo, NULL, NULL,
+                                         getGroupSortExplainExecInfo);
+
+  int32_t code = appendDownstream(pOperator, &downstream, 1);
+  if (code != TSDB_CODE_SUCCESS) {
+    goto _error;
+  }
+
+  return pOperator;
+
+_error:
+  pTaskInfo->code = TSDB_CODE_OUT_OF_MEMORY;
+  taosMemoryFree(pInfo);
+  taosMemoryFree(pOperator);
+  return NULL;
+}
+
+void destroyGroupSortOperatorInfo(void* param, int32_t numOfOutput) {
+  SGroupSortOperatorInfo* pInfo = (SGroupSortOperatorInfo*)param;
+  pInfo->binfo.pRes = blockDataDestroy(pInfo->binfo.pRes);
+
+  taosArrayDestroy(pInfo->pSortInfo);
+  taosArrayDestroy(pInfo->pColMatchInfo);
+}
+
+
+//TODO: sort group
+//TODO: msortCompare compare group id in multiway merge sort.
+//TODO: table merge scan, group first, then for each group, multiple readers
+
+//=====================================================================================
+// Multiway Sort Merge operator
 typedef struct SMultiwaySortMergeOperatorInfo {
   SOptrBasicInfo binfo;