diff --git a/source/dnode/vnode/src/tsdb/tsdbMerge.c b/source/dnode/vnode/src/tsdb/tsdbMerge.c
index 0c20a342d3..0db8cf85ed 100644
--- a/source/dnode/vnode/src/tsdb/tsdbMerge.c
+++ b/source/dnode/vnode/src/tsdb/tsdbMerge.c
@@ -483,11 +483,12 @@ _exit:
 }
 
 static int32_t tsdbDoMerge(SMerger *merger) {
-  int32_t  code = 0;
-  int32_t  lino = 0;
-  SSttLvl *lvl = TARRAY2_FIRST(merger->fset->lvlArr);
+  int32_t code = 0;
+  int32_t lino = 0;
 
   if (TARRAY2_SIZE(merger->fset->lvlArr) == 0) return 0;
+
+  SSttLvl *lvl = TARRAY2_FIRST(merger->fset->lvlArr);
   if (lvl->level != 0 || TARRAY2_SIZE(lvl->fobjArr) < merger->sttTrigger) return 0;
 
   code = tsdbMergerOpen(merger);