diff --git a/src/sql/engine/sort/ob_sort_op_impl.cpp b/src/sql/engine/sort/ob_sort_op_impl.cpp
index 94d2247c7c..b0d04bc4b7 100644
--- a/src/sql/engine/sort/ob_sort_op_impl.cpp
+++ b/src/sql/engine/sort/ob_sort_op_impl.cpp
@@ -1423,11 +1423,10 @@ int ObSortOpImpl::prepare_bucket_array(ArrayType *&buckets, uint64_t bucket_num)
   } else {
     int64_t max_bucket_cnt  = buckets->get_capacity();
     if (max_bucket_cnt < bucket_num) {
-      if (OB_FAIL(buckets->reserve(bucket_num))) {
-        LOG_WARN("failed to reserve bucket array", K(ret), K(bucket_num));
-      }
-    } else {
       buckets->reuse();
+      if (OB_FAIL(buckets->init(bucket_num))) {
+        LOG_WARN("failed to init bucket array", K(ret), K(bucket_num));
+      }
     }
   }
   return ret;
@@ -1455,6 +1454,7 @@ int ObSortOpImpl::do_partition_sort(common::ObIArray<ObChunkDatumStore::StoredRo
     } else if (OB_FAIL(prepare_bucket_array<BucketNodeArray>(part_hash_nodes_, node_cnt))) {
       LOG_WARN("failed to create bucket node array", K(ret));
     } else {
+      buckets_->set_all(nullptr);
       max_bucket_cnt_ = bucket_cnt;
       max_node_cnt_ = node_cnt;
     }
diff --git a/src/sql/engine/sort/ob_sort_vec_op_impl.h b/src/sql/engine/sort/ob_sort_vec_op_impl.h
index 6506329dbd..7052e67d03 100644
--- a/src/sql/engine/sort/ob_sort_vec_op_impl.h
+++ b/src/sql/engine/sort/ob_sort_vec_op_impl.h
@@ -383,11 +383,10 @@ protected:
     } else {
       int64_t max_bucket_cnt = buckets->get_capacity();
       if (max_bucket_cnt < bucket_num) {
-        if (OB_FAIL(buckets->reserve(bucket_num))) {
-          LOG_WARN("failed to reserve bucket array", K(ret), K(bucket_num));
-        }
-      } else {
         buckets->reuse();
+        if (OB_FAIL(buckets->init(bucket_num))) {
+          LOG_WARN("failed to init bucket array", K(ret), K(bucket_num));
+        }
       }
     }
     return ret;
diff --git a/src/sql/engine/sort/ob_sort_vec_op_impl.ipp b/src/sql/engine/sort/ob_sort_vec_op_impl.ipp
index aae09ba9b7..d2abc01172 100644
--- a/src/sql/engine/sort/ob_sort_vec_op_impl.ipp
+++ b/src/sql/engine/sort/ob_sort_vec_op_impl.ipp
@@ -1309,6 +1309,7 @@ int ObSortVecOpImpl<Compare, Store_Row, has_addon>::do_partition_sort(
     } else if (OB_FAIL(prepare_bucket_array<BucketNodeArray>(part_hash_nodes_, node_cnt))) {
       LOG_WARN("failed to create bucket node array", K(ret));
     } else {
+      buckets_->set_all(nullptr);
       max_bucket_cnt_ = bucket_cnt;
       max_node_cnt_ = node_cnt;
     }