mixed 8562 pr

src/client/src/tscUtil.c

@@ -942,23 +942,30 @@ SSDataBlock* doGetDataBlock(void* param, bool* newgroup) {
   pBlock->info.rows = pRes->numOfRows;
   if (pRes->numOfRows != 0) {
     doSetupSDataBlock(pRes, pBlock, pInput->pFilterInfo);
+    if (pBlock->info.rows > 0) {
       *newgroup = false;
       return pBlock;
     }
+  }
 
+  SSDataBlock* result = NULL;
+  do {
     // No data block exists. So retrieve and transfer it into to SSDataBlock
     TAOS_ROW pRow = NULL;
     taos_fetch_block(pSql, &pRow);
 
     if (pRes->numOfRows == 0) {
       pOperator->status = OP_EXEC_DONE;
-    return NULL;
+      result = NULL;
+      break;
     }
-
     pBlock->info.rows = pRes->numOfRows;
     doSetupSDataBlock(pRes, pBlock, pInput->pFilterInfo);
     *newgroup = false;
-  return pBlock;
+    result = pBlock;
+  } while (result->info.rows == 0);
+
+  return result;
 }
 
 static void fetchNextBlockIfCompleted(SOperatorInfo* pOperator, bool* newgroup) {