diff --git a/src/query/inc/qExtbuffer.h b/src/query/inc/qExtbuffer.h
index 9938f599ed2f3a5844b386b13cd95da5951a45f0..509549ba22842a200f5efbb69ff0f73237b31737 100644
--- a/src/query/inc/qExtbuffer.h
+++ b/src/query/inc/qExtbuffer.h
@@ -227,8 +227,6 @@ tOrderDescriptor *tOrderDesCreate(const int32_t *orderColIdx, int32_t numOfOrder
 
 void tOrderDescDestroy(tOrderDescriptor *pDesc);
 
-void taoscQSort(void** pCols, SSchema* pSchema, int32_t numOfCols, int32_t numOfRows, int32_t index, __compar_fn_t compareFn);
-
 void tColModelAppend(SColumnModel *dstModel, tFilePage *dstPage, void *srcData, int32_t srcStartRows,
                      int32_t numOfRowsToWrite, int32_t srcCapacity);
 
@@ -239,7 +237,7 @@ void tColDataQSort(tOrderDescriptor *, int32_t numOfRows, int32_t start, int32_t
 void tColDataMergeSort(tOrderDescriptor *, int32_t numOfRows, int32_t start, int32_t end, char *data, int32_t orderType);
 
 
-void taoscQSort(void** pCols, SSchema* pSchema, int32_t numOfCols, int32_t numOfRows, int32_t index, __compar_fn_t compareFn);
+int32_t taoscQSort(void** pCols, SSchema* pSchema, int32_t numOfCols, int32_t numOfRows, int32_t index, __compar_fn_t compareFn);
 
 int32_t compare_sa(tOrderDescriptor *, int32_t numOfRows, int32_t idx1, int32_t idx2, char *data);
 
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 9424200840f4599bc6bb67e80396c5587bb7d811..dc2837869f5da82129d5c64cd9595d88c4d81e03 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -5959,7 +5959,13 @@ static SSDataBlock* doSort(void* param, bool* newgroup) {
 
   __compar_fn_t  comp = getKeyComparFunc(pSchema[pInfo->colIndex].type, pInfo->order);
   if (pInfo->pDataBlock->info.rows) {
-    taoscQSort(pCols, pSchema, numOfCols, pInfo->pDataBlock->info.rows, pInfo->colIndex, comp);
+    int32_t code = taoscQSort(pCols, pSchema, numOfCols, pInfo->pDataBlock->info.rows, pInfo->colIndex, comp);
+    if (code != TSDB_CODE_SUCCESS) {
+      qError("QInfo:0x%"PRIx64 " can not sort since %s", GET_QID(pOperator->pRuntimeEnv), tstrerror(code));
+      tfree(pCols);
+      tfree(pSchema);
+      longjmp(pOperator->pRuntimeEnv->env, code);
+    }
   }
   
   tfree(pCols);
diff --git a/src/query/src/qExtbuffer.c b/src/query/src/qExtbuffer.c
index d49d6ecf0b582ba60674d8a3e7a482bf8d969238..f3fcab9ff73c9365a70d82d02ab5ccc973700472 100644
--- a/src/query/src/qExtbuffer.c
+++ b/src/query/src/qExtbuffer.c
@@ -1246,7 +1246,7 @@ void tOrderDescDestroy(tOrderDescriptor *pDesc) {
   tfree(pDesc);
 }
 
-void taoscQSort(void** pCols, SSchema* pSchema, int32_t numOfCols, int32_t numOfRows, int32_t idx, __compar_fn_t compareFn) {
+int32_t taoscQSort(void** pCols, SSchema* pSchema, int32_t numOfCols, int32_t numOfRows, int32_t idx, __compar_fn_t compareFn) {
   assert(numOfRows > 0 && numOfCols > 0 && idx >= 0 && idx < numOfCols);
 
   int32_t bytes = pSchema[idx].bytes;
@@ -1278,7 +1278,12 @@ void taoscQSort(void** pCols, SSchema* pSchema, int32_t numOfCols, int32_t numOf
       // make sure memory buffer is enough
       if (prevLength < bytes1) {
         char *tmp = realloc(p, bytes1 * numOfRows);
-        assert(tmp);
+        if (tmp == NULL) {
+          qError("can not allocated memory. bytes:%d", bytes*numOfRows);
+          tfree(p);
+          tfree(buf);
+          return TSDB_CODE_QRY_OUT_OF_MEMORY;
+        }
 
         p = tmp;
         prevLength = bytes1;
@@ -1298,4 +1303,5 @@ void taoscQSort(void** pCols, SSchema* pSchema, int32_t numOfCols, int32_t numOf
 
   tfree(buf);
   tfree(p);
+  return TSDB_CODE_SUCCESS;
 }