diff --git a/src/query/inc/qUtil.h b/src/query/inc/qUtil.h
index 4cd0e60ebed3bc01c40fa8bee1a255fe9d0b132f..b2c4b6e2ec2c8e1d073ebca4ded627baf9f9ae4a 100644
--- a/src/query/inc/qUtil.h
+++ b/src/query/inc/qUtil.h
@@ -80,5 +80,7 @@ void* destroyResultRowPool(SResultRowPool* p);
 int32_t getNumOfAllocatedResultRows(SResultRowPool* p);
 int32_t getNumOfUsedResultRows(SResultRowPool* p);
 
+uint64_t getResultInfoUId(SQueryRuntimeEnv* pRuntimeEnv);
+
 
 #endif  // TDENGINE_QUERYUTIL_H
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index d0874c36bc1783242c8536ebeec1fbce8559389f..c44d65e37330e38f1af1fc531379a168f85bfb30 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -186,7 +186,7 @@ static void setExecParams(SQuery *pQuery, SQLFunctionCtx *pCtx, void* inputData,
 
 static void initCtxOutputBuf(SQueryRuntimeEnv *pRuntimeEnv);
 static void destroyTableQueryInfoImpl(STableQueryInfo *pTableQueryInfo);
-static void resetCtxOutputBuf(SQueryRuntimeEnv *pRuntimeEnv);
+static void resetDefaultResInfoOutputBuf(SQueryRuntimeEnv *pRuntimeEnv);
 static bool hasMainOutput(SQuery *pQuery);
 static void buildTagQueryResult(SQInfo *pQInfo);
 
@@ -283,8 +283,8 @@ void updateNumOfResult(SQueryRuntimeEnv *pRuntimeEnv, int32_t numOfRes) {
   }
 }
 
-static UNUSED_FUNC int32_t getGroupResultId(int32_t groupIndex) {
-  int32_t base = 20000000;
+static int32_t getMergeResultGroupId(int32_t groupIndex) {
+  int32_t base = 50000000;
   return base + (groupIndex * 10000);
 }
 
@@ -1115,7 +1115,7 @@ static int32_t setGroupResultOutputBuf(SQueryRuntimeEnv *pRuntimeEnv, char *pDat
 
   SDiskbasedResultBuf *pResultBuf = pRuntimeEnv->pResultBuf;
 
-  // not assign result buffer yet, add new result buffer
+  // not assign result buffer yet, add new result buffer, TODO remove it
   char* d = pData;
   int16_t len = bytes;
   if (type == TSDB_DATA_TYPE_BINARY||type == TSDB_DATA_TYPE_NCHAR) {
@@ -1128,7 +1128,7 @@ static int32_t setGroupResultOutputBuf(SQueryRuntimeEnv *pRuntimeEnv, char *pDat
     longjmp(pRuntimeEnv->env, TSDB_CODE_QRY_APP_ERROR);
   }
 
-  uint64_t uid = groupIndex; // uid is always set to be 0.
+  uint64_t uid = groupIndex;
   SResultRow *pResultRow = doPrepareResultRowFromKey(pRuntimeEnv, &pRuntimeEnv->windowResInfo, d, len, true, uid);
   if (pResultRow == NULL) {
     return -1;
@@ -1714,7 +1714,7 @@ static int32_t setupQueryRuntimeEnv(SQueryRuntimeEnv *pRuntimeEnv, int16_t order
   // if it is group by normal column, do not set output buffer, the output buffer is pResult
   // fixed output query/multi-output query for normal table
   if (!pRuntimeEnv->groupbyNormalCol && !pRuntimeEnv->stableQuery && !QUERY_IS_INTERVAL_QUERY(pRuntimeEnv->pQuery)) {
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
   }
 
   if (setCtxTagColumnInfo(pRuntimeEnv, pRuntimeEnv->pCtx) != TSDB_CODE_SUCCESS) {
@@ -2936,10 +2936,24 @@ void copyResToQueryResultBuf(SQInfo *pQInfo, SQuery *pQuery) {
   assert(size == pGroupResInfo->numOfDataPages);
 
   bool done = false;
+
+  //TODO add API for release none-dirty pages
+//  SPageInfo* prev = NULL;
+
   for (int32_t j = pGroupResInfo->pageId; j < size; ++j) {
     SPageInfo* pi = *(SPageInfo**) taosArrayGet(list, j);
     tFilePage* pData = getResBufPage(pResultBuf, pi->pageId);
 
+    // release previous buffer pages
+//    if (prev == NULL) {
+//      prev = pi;
+//    } else {
+//      if (prev->pageId != pi->pageId) {
+//        releaseResBufPageInfo(pResultBuf, prev);
+//        prev = pi;
+//      }
+//    }
+
     assert(pData->num > 0 && pData->num <= pRuntimeEnv->numOfRowsPerPage && pGroupResInfo->rowId < pData->num);
     int32_t numOfRes = (int32_t)(pData->num - pGroupResInfo->rowId);
 
@@ -3058,7 +3072,7 @@ int32_t mergeIntoGroupResultImpl(SQInfo *pQInfo, SArray *pGroup) {
   SResultRow* pRow = getNewResultRow(pRuntimeEnv->pool);
   resetMergeResultBuf(pRuntimeEnv, pRuntimeEnv->pCtx, pRow);
 
-  pQInfo->groupResInfo.groupId = getGroupResultId(pQInfo->groupIndex);
+  pQInfo->groupResInfo.groupId = getMergeResultGroupId(pQInfo->groupIndex);
 
   // todo add windowRes iterator
   int64_t lastTimestamp = -1;
@@ -3339,12 +3353,12 @@ int32_t initResultRow(SResultRow *pResultRow) {
   return TSDB_CODE_SUCCESS;
 }
 
-void resetCtxOutputBuf(SQueryRuntimeEnv *pRuntimeEnv) {
+void resetDefaultResInfoOutputBuf(SQueryRuntimeEnv *pRuntimeEnv) {
   SQuery *pQuery = pRuntimeEnv->pQuery;
 
-  int32_t groupIndex = 0;
-  int32_t uid = 0;
-  SResultRow* pRow = doPrepareResultRowFromKey(pRuntimeEnv, &pRuntimeEnv->windowResInfo, (char *)&groupIndex, sizeof(groupIndex), true, uid);
+  int32_t tid = 0;
+  int64_t uid = getResultInfoUId(pRuntimeEnv);
+  SResultRow* pRow = doPrepareResultRowFromKey(pRuntimeEnv, &pRuntimeEnv->windowResInfo, (char *)&tid, sizeof(tid), true, uid);
 
   for (int32_t i = 0; i < pQuery->numOfOutput; ++i) {
     SQLFunctionCtx *pCtx = &pRuntimeEnv->pCtx[i];
@@ -3427,7 +3441,7 @@ void skipResults(SQueryRuntimeEnv *pRuntimeEnv) {
     pQuery->limit.offset -= pQuery->rec.rows;
     pQuery->rec.rows = 0;
 
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
 
     // clear the buffer full flag if exists
     CLEAR_QUERY_STATUS(pQuery, QUERY_RESBUF_FULL);
@@ -3792,7 +3806,7 @@ void setExecutionContext(SQInfo *pQInfo, int32_t groupIndex, TSKEY nextKey) {
     return;
   }
 
-  uint64_t uid = 0; // uid is always set to be 0
+  uint64_t uid = getResultInfoUId(pRuntimeEnv);
   SResultRow *pResultRow = doPrepareResultRowFromKey(pRuntimeEnv, pWindowResInfo, (char *)&groupIndex,
       sizeof(groupIndex), true, uid);
   if (pResultRow == NULL) {
@@ -4629,10 +4643,10 @@ int32_t doInitQInfo(SQInfo *pQInfo, STSBuf *pTsBuf, void *tsdb, int32_t vgId, bo
   int32_t ps = DEFAULT_PAGE_SIZE;
   int32_t rowsize = 0;
   getIntermediateBufInfo(pRuntimeEnv, &ps, &rowsize);
-  int32_t TWOMB = 1024*1024*2;
+  int32_t TENMB = 1024*1024*10;
 
   if (isSTableQuery && !onlyQueryTags(pRuntimeEnv->pQuery)) {
-    code = createDiskbasedResultBuffer(&pRuntimeEnv->pResultBuf, rowsize, ps, TWOMB, pQInfo);
+    code = createDiskbasedResultBuffer(&pRuntimeEnv->pResultBuf, rowsize, ps, TENMB, pQInfo);
     if (code != TSDB_CODE_SUCCESS) {
       return code;
     }
@@ -4660,7 +4674,7 @@ int32_t doInitQInfo(SQInfo *pQInfo, STSBuf *pTsBuf, void *tsdb, int32_t vgId, bo
   } else if (pRuntimeEnv->groupbyNormalCol || QUERY_IS_INTERVAL_QUERY(pQuery) || (!isSTableQuery)) {
     int32_t numOfResultRows = getInitialPageNum(pQInfo);
     getIntermediateBufInfo(pRuntimeEnv, &ps, &rowsize);
-    code = createDiskbasedResultBuffer(&pRuntimeEnv->pResultBuf, rowsize, ps, TWOMB, pQInfo);
+    code = createDiskbasedResultBuffer(&pRuntimeEnv->pResultBuf, rowsize, ps, TENMB, pQInfo);
     if (code != TSDB_CODE_SUCCESS) {
       return code;
     }
@@ -4930,7 +4944,7 @@ static void sequentialTableProcess(SQInfo *pQInfo) {
   size_t numOfGroups = GET_NUM_OF_TABLEGROUP(pQInfo);
 
   if (isPointInterpoQuery(pQuery)) {
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
     assert(pQuery->limit.offset == 0 && pQuery->limit.limit != 0);
 
     while (pQInfo->groupIndex < numOfGroups) {
@@ -5096,7 +5110,7 @@ static void sequentialTableProcess(SQInfo *pQInfo) {
       return;
     }
 
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
     resetTimeWindowInfo(pRuntimeEnv, &pRuntimeEnv->windowResInfo);
 
     SArray *group = GET_TABLEGROUP(pQInfo, 0);
@@ -5456,7 +5470,7 @@ static void tableMultiOutputProcess(SQInfo *pQInfo, STableQueryInfo* pTableInfo)
 
   // for ts_comp query, re-initialized is not allowed
   if (!isTSCompQuery(pQuery)) {
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
   }
 
   // skip blocks without load the actual data block from file if no filter condition present
@@ -5486,7 +5500,7 @@ static void tableMultiOutputProcess(SQInfo *pQInfo, STableQueryInfo* pTableInfo)
     qDebug("QInfo:%p skip current result, offset:%" PRId64 ", next qrange:%" PRId64 "-%" PRId64,
            pQInfo, pQuery->limit.offset, pQuery->current->lastKey, pQuery->current->win.ekey);
 
-    resetCtxOutputBuf(pRuntimeEnv);
+    resetDefaultResInfoOutputBuf(pRuntimeEnv);
   }
 
   limitResults(pRuntimeEnv);
diff --git a/src/query/src/qResultbuf.c b/src/query/src/qResultbuf.c
index c5ba551f204d72424e11f3e0ef29029a03e1c207..67cb7af074b1982eb322ebf311d2c337bfa5fc55 100644
--- a/src/query/src/qResultbuf.c
+++ b/src/query/src/qResultbuf.c
@@ -407,7 +407,7 @@ void destroyResultBuf(SDiskbasedResultBuf* pResultBuf) {
   }
 
   if (pResultBuf->file != NULL) {
-    qDebug("QInfo:%p res output buffer closed, total:%.2f Kb, inmem size:%.2f Kb, file size:%.2f",
+    qDebug("QInfo:%p res output buffer closed, total:%.2f Kb, inmem size:%.2f Kb, file size:%.2f Kb",
         pResultBuf->handle, pResultBuf->totalBufSize/1024.0, listNEles(pResultBuf->lruList) * pResultBuf->pageSize / 1024.0,
         pResultBuf->fileSize/1024.0);
 
diff --git a/src/query/src/qUtil.c b/src/query/src/qUtil.c
index c5317226c7c9a8113395a5ae9502ff1835043acb..650b886c36029bae989767eaa6a30e0c6e1530cf 100644
--- a/src/query/src/qUtil.c
+++ b/src/query/src/qUtil.c
@@ -20,6 +20,18 @@
 #include "qExecutor.h"
 #include "qUtil.h"
 
+static int32_t getResultRowKeyInfo(SResultRow* pResult, int16_t type, char** key, int16_t* bytes) {
+  if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
+    *key   = varDataVal(pResult->key);
+    *bytes = varDataLen(pResult->key);
+  } else {
+    *key = (char*) &pResult->win.skey;
+    *bytes = tDataTypeDesc[type].nSize;
+  }
+
+  return 0;
+}
+
 int32_t getOutputInterResultBufSize(SQuery* pQuery) {
   int32_t size = 0;
 
@@ -94,12 +106,8 @@ void clearFirstNWindowRes(SQueryRuntimeEnv *pRuntimeEnv, int32_t num) {
   int32_t numOfClosed = numOfClosedTimeWindow(pWindowResInfo);
   assert(num >= 0 && num <= numOfClosed);
 
-  int16_t  type = pWindowResInfo->type;
-  STableId* id  = TSDB_TABLEID(pRuntimeEnv->pQuery->current->pTable); // uid is always set to be 0.
-  int64_t uid = id->uid;
-  if (pRuntimeEnv->groupbyNormalCol) {
-    uid = 0;
-  }
+  int16_t type = pWindowResInfo->type;
+  int64_t uid = getResultInfoUId(pRuntimeEnv);
 
   char    *key  = NULL;
   int16_t  bytes = -1;
@@ -107,16 +115,7 @@ void clearFirstNWindowRes(SQueryRuntimeEnv *pRuntimeEnv, int32_t num) {
   for (int32_t i = 0; i < num; ++i) {
     SResultRow *pResult = pWindowResInfo->pResult[i];
     if (pResult->closed) {  // remove the window slot from hash table
-
-      // todo refactor
-      if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
-        key   = varDataVal(pResult->key);
-        bytes = varDataLen(pResult->key);
-      } else {
-        key = (char*) &pResult->win.skey;
-        bytes = tDataTypeDesc[pWindowResInfo->type].nSize;
-      }
-
+      getResultRowKeyInfo(pResult, type, &key, &bytes);
       SET_RES_WINDOW_KEY(pRuntimeEnv->keyBuf, key, bytes, uid);
       taosHashRemove(pRuntimeEnv->pResultRowHashTable, (const char *)pRuntimeEnv->keyBuf, GET_RES_WINDOW_KEY_LEN(bytes));
     } else {
@@ -141,16 +140,9 @@ void clearFirstNWindowRes(SQueryRuntimeEnv *pRuntimeEnv, int32_t num) {
 
   for (int32_t k = 0; k < pWindowResInfo->size; ++k) {
     SResultRow *pResult = pWindowResInfo->pResult[k];
-
-    if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
-      key = varDataVal(pResult->key);
-      bytes = varDataLen(pResult->key);
-    } else {
-      key = (char*) &pResult->win.skey;
-      bytes = tDataTypeDesc[pWindowResInfo->type].nSize;
-    }
-
+    getResultRowKeyInfo(pResult, type, &key, &bytes);
     SET_RES_WINDOW_KEY(pRuntimeEnv->keyBuf, key, bytes, uid);
+
     int32_t *p = (int32_t *)taosHashGet(pRuntimeEnv->pResultRowHashTable, (const char *)pRuntimeEnv->keyBuf, GET_RES_WINDOW_KEY_LEN(bytes));
     assert(p != NULL); 
 
@@ -379,3 +371,12 @@ void* destroyResultRowPool(SResultRowPool* p) {
   tfree(p);
   return NULL;
 }
+
+uint64_t getResultInfoUId(SQueryRuntimeEnv* pRuntimeEnv) {
+  if (!pRuntimeEnv->stableQuery) {
+    return 0;  // for simple table query, the uid is always set to be 0;
+  }
+
+  STableId* id = TSDB_TABLEID(pRuntimeEnv->pQuery->current);
+  return id->uid;
+}
\ No newline at end of file