diff --git a/source/dnode/vnode/src/tsdb/tsdbRead.c b/source/dnode/vnode/src/tsdb/tsdbRead.c
index 1f200ea5d79a221d80265ce86fb927a1694a33e1..986cba8b17b17936d3dc0ded647824638a5f1101 100644
--- a/source/dnode/vnode/src/tsdb/tsdbRead.c
+++ b/source/dnode/vnode/src/tsdb/tsdbRead.c
@@ -4128,7 +4128,8 @@ int32_t tsdbRetrieveDatablockSMA(STsdbReader* pReader, SColumnDataAgg*** pBlockS
   taosArrayClear(pSup->pColAgg);
   taosArrayAddAll(pSup->pColAgg, pNewAggList);
 
-  for(int32_t k = 0; k < numOfCols; ++k) {
+  size_t num = taosArrayGetSize(pSup->pColAgg);
+  for(int32_t k = 0; k < num; ++k) {
     pSup->plist[k] = taosArrayGet(pSup->pColAgg, k);
   }