diff --git a/src/client/src/tscSubquery.c b/src/client/src/tscSubquery.c
index ed9e0f7d32e255eab1fb7ee8560a421b7a50cbb8..a9197a33f15c39d34fd38696d59b8e2ba8ab5521 100644
--- a/src/client/src/tscSubquery.c
+++ b/src/client/src/tscSubquery.c
@@ -3351,10 +3351,14 @@ static void tscRetrieveFromDnodeCallBack(void *param, TAOS_RES *tres, int numOfR
     }
 
     SColumnModel *pModelDesc = pDesc->pColumnModel;
+    if (pModelDesc == NULL) {
+      tscError("0x%"PRIx64" sub:0x%"PRIx64" column model has been freed", pParentSql->self, pSql->self);
+      tscAbortFurtherRetryRetrieval(trsupport, tres, TSDB_CODE_QRY_APP_ERROR);
+    }
     SColumnModel *pModelMemBuf = trsupport->pExtMemBuffer[idx]->pColumnModel;
     if (pModelDesc->numOfCols != pModelMemBuf->numOfCols ||
         pModelDesc->rowSize != pModelMemBuf->rowSize) {
-      tscError("extBuf column model is not consistent with descriptor column model");
+      tscError("0x%"PRIx64" sub:0x%"PRIx64 "extBuf column model is not consistent with descriptor column model", pParentSql->self, pSql->self);
       tscAbortFurtherRetryRetrieval(trsupport, tres, TSDB_CODE_QRY_APP_ERROR);
       return;
     }
diff --git a/src/query/src/qExtbuffer.c b/src/query/src/qExtbuffer.c
index fa0b891df0bc06c621a02740d538ef69b04ea6fd..fa376097fcfbc4c50b2436652a3f62daff02d722 100644
--- a/src/query/src/qExtbuffer.c
+++ b/src/query/src/qExtbuffer.c
@@ -1254,6 +1254,7 @@ void tOrderDescDestroy(tOrderDescriptor *pDesc) {
   }
 
   destroyColumnModel(pDesc->pColumnModel);
+  pDesc->pColumnModel = NULL;
   tfree(pDesc);
 }