diff --git a/source/dnode/vnode/src/tsdb/tsdbRead.c b/source/dnode/vnode/src/tsdb/tsdbRead.c
index 4686d97ec881aab75455c9e7e44a61bd02a8fcf1..1331fcf30ae93b6c95864fe22eed185064bf591f 100644
--- a/source/dnode/vnode/src/tsdb/tsdbRead.c
+++ b/source/dnode/vnode/src/tsdb/tsdbRead.c
@@ -1410,30 +1410,33 @@ static int32_t doCopyRowsFromFileBlock(STsdbReadHandle* pTsdbReadHandle, int32_t
     if (!isAllRowsNull(src) && pColInfo->info.colId == src->colId) {
       if (!IS_VAR_DATA_TYPE(pColInfo->info.type)) {  // todo opt performance
         //        memmove(pData, (char*)src->pData + bytes * start, bytes * num);
-        for (int32_t k = start; k < num + start; ++k) {
+        int32_t rowIndex = numOfRows;
+        for (int32_t k = start; k <= end; ++k, ++rowIndex) {
           SCellVal sVal = {0};
           if (tdGetColDataOfRow(&sVal, src, k, pCols->bitmapMode) < 0) {
             TASSERT(0);
           }
 
           if (sVal.valType == TD_VTYPE_NULL) {
-            colDataAppendNULL(pColInfo, k);
+            colDataAppendNULL(pColInfo, rowIndex);
           } else {
-            colDataAppend(pColInfo, k, sVal.val, false);
+            colDataAppend(pColInfo, rowIndex, sVal.val, false);
           }
         }
       } else {  // handle the var-string
+        int32_t rowIndex = numOfRows;
+
         // todo refactor, only copy one-by-one
-        for (int32_t k = start; k < num + start; ++k) {
+        for (int32_t k = start; k < num + start; ++k, ++rowIndex) {
           SCellVal sVal = {0};
           if (tdGetColDataOfRow(&sVal, src, k, pCols->bitmapMode) < 0) {
             TASSERT(0);
           }
 
           if (sVal.valType == TD_VTYPE_NULL) {
-            colDataAppendNULL(pColInfo, k);
+            colDataAppendNULL(pColInfo, rowIndex);
           } else {
-            colDataAppend(pColInfo, k, sVal.val, false);
+            colDataAppend(pColInfo, rowIndex, sVal.val, false);
           }
         }
       }
@@ -1441,8 +1444,9 @@ static int32_t doCopyRowsFromFileBlock(STsdbReadHandle* pTsdbReadHandle, int32_t
       j++;
       i++;
     } else {                                           // pColInfo->info.colId < src->colId, it is a NULL data
-      for (int32_t k = start; k < num + start; ++k) {  // TODO opt performance
-        colDataAppend(pColInfo, k, NULL, true);
+      int32_t rowIndex = numOfRows;
+      for (int32_t k = start; k < num + start; ++k, ++rowIndex) {  // TODO opt performance
+        colDataAppend(pColInfo, rowIndex, NULL, true);
       }
       i++;
     }
@@ -1450,8 +1454,10 @@ static int32_t doCopyRowsFromFileBlock(STsdbReadHandle* pTsdbReadHandle, int32_t
 
   while (i < requiredNumOfCols) {  // the remain columns are all null data
     SColumnInfoData* pColInfo = taosArrayGet(pTsdbReadHandle->pColumns, i);
-    for (int32_t k = start; k < num + start; ++k) {
-      colDataAppend(pColInfo, k, NULL, true);  // TODO add a fast version to set a number of consecutive NULL value.
+    int32_t rowIndex = numOfRows;
+
+    for (int32_t k = start; k < num + start; ++k, ++rowIndex) {
+      colDataAppend(pColInfo, rowIndex, NULL, true);  // TODO add a fast version to set a number of consecutive NULL value.
     }
     i++;
   }
@@ -1749,7 +1755,7 @@ int32_t getEndPosInDataBlock(STsdbReadHandle* pTsdbReadHandle, SDataBlockInfo* p
 // be included in the query time window will be discarded
 static void doMergeTwoLevelData(STsdbReadHandle* pTsdbReadHandle, STableCheckInfo* pCheckInfo, SBlock* pBlock) {
   SQueryFilePos* cur = &pTsdbReadHandle->cur;
-  SDataBlockInfo blockInfo = {0};  // GET_FILE_DATA_BLOCK_INFO(pCheckInfo, pBlock);
+  SDataBlockInfo blockInfo = GET_FILE_DATA_BLOCK_INFO(pCheckInfo, pBlock);
   STsdbCfg*      pCfg = &pTsdbReadHandle->pTsdb->config;
 
   initTableMemIterator(pTsdbReadHandle, pCheckInfo);
@@ -1771,9 +1777,7 @@ static void doMergeTwoLevelData(STsdbReadHandle* pTsdbReadHandle, STableCheckInf
   STable* pTable = NULL;
   int32_t endPos = getEndPosInDataBlock(pTsdbReadHandle, &blockInfo);
 
-  tsdbDebug("%p uid:%" PRIu64 " start merge data block, file block range:%" PRIu64 "-%" PRIu64
-            " rows:%d, start:%d,"
-            "end:%d, %s",
+  tsdbDebug("%p uid:%" PRIu64 " start merge data block, file block range:%" PRIu64 "-%" PRIu64 " rows:%d, start:%d, end:%d, %s",
             pTsdbReadHandle, pCheckInfo->tableId, blockInfo.window.skey, blockInfo.window.ekey, blockInfo.rows,
             cur->pos, endPos, pTsdbReadHandle->idStr);