diff --git a/source/libs/executor/src/scanoperator.c b/source/libs/executor/src/scanoperator.c
index 0ed41aeea1..df2062afe6 100644
--- a/source/libs/executor/src/scanoperator.c
+++ b/source/libs/executor/src/scanoperator.c
@@ -2113,6 +2113,8 @@ FETCH_NEXT_BLOCK:
         pBlock->info.dataLoad = 1;
         blockDataUpdateTsWindow(pBlock, pInfo->primaryTsIndex);
 
+        qDebug("%" PRId64 " rows in datablock, update res:%" PRId64 " %s", pBlockInfo->rows,
+               pInfo->pUpdateDataRes->info.rows, id);
         if (pBlockInfo->rows > 0 || pInfo->pUpdateDataRes->info.rows > 0) {
           break;
         }