diff --git a/src/query/src/qExtbuffer.c b/src/query/src/qExtbuffer.c
index 7d15520cc693ca1af0dbec1d4c1b73a522d7434b..ef4b56dc877ca75fe79ac5a345e99e0a3717eff5 100644
--- a/src/query/src/qExtbuffer.c
+++ b/src/query/src/qExtbuffer.c
@@ -859,7 +859,7 @@ void tColDataMergeSort(tOrderDescriptor *pDescriptor, int32_t numOfRows, int32_t
 
   size_t width = 0;
   for(int32_t i = 0; i < pModel->numOfCols; ++i) {
-    SSchema* pSchema = &pModel->pFields[i].field;
+    SSchema1* pSchema = &pModel->pFields[i].field;
     if (width < pSchema->bytes) {
       width = pSchema->bytes;
     }