diff --git a/src/storage/ob_partition_storage.cpp b/src/storage/ob_partition_storage.cpp
index da9db2c2a..174f33ed1 100644
--- a/src/storage/ob_partition_storage.cpp
+++ b/src/storage/ob_partition_storage.cpp
@@ -7364,6 +7364,7 @@ int ObPartitionStorage::append_local_sort_data(const share::ObBuildIndexAppendLo
                      pg_key,
                      file_handle))) {
         STORAGE_LOG(WARN, "Fail to init data store desc, ", K(ret));
+      } else if (FALSE_IT(data_desc.is_unique_index_ = index_schema->is_unique_index())) {
       } else if (OB_FAIL(writer.open(data_desc, ObMacroDataSeq((INT64_MAX / param.task_cnt_) * param.task_id_)))) {
         STORAGE_LOG(WARN, "Fail to open macro block writer, ", K(ret));
       } else {