diff --git a/src/sql/parser/parse_node.c b/src/sql/parser/parse_node.c
index e1df5509743404afd99f56d85b8d759b32a5eb5e..fef2af133fbe9d9992459e01c1189c280633c0a3 100644
--- a/src/sql/parser/parse_node.c
+++ b/src/sql/parser/parse_node.c
@@ -129,7 +129,7 @@ int count_child(ParseNode* root, void* malloc_pool, int* count)
     do {
       ParseNode *tree = NULL;
       if (NULL == stack_top || NULL == (tree = (ParseNode *)stack_top->val_)) {
-        ret = OB_PARSER_ERR_NO_MEMORY;
+        ret = OB_PARSER_ERR_UNEXPECTED;
         (void)fprintf(stderr, "ERROR invalid null argument\n");
       } else {
         stack_top = stack_top->next_;
@@ -142,7 +142,7 @@ int count_child(ParseNode* root, void* malloc_pool, int* count)
         // do nothing
       } else {
         if (NULL == tree->children_) {
-          ret = OB_PARSER_ERR_NO_MEMORY;
+          ret = OB_PARSER_ERR_UNEXPECTED;
           (void)fprintf(stderr, "ERROR invalid null children\n");
         }
         ParserLinkNode* tmp_node = NULL;
@@ -171,7 +171,7 @@ int merge_child(ParseNode* node, void* malloc_pool, ParseNode* source_tree, int*
   int ret = 0;
   ParserLinkNode* stack_top = NULL;
   if (OB_UNLIKELY(NULL == node || NULL == index)) {
-    ret = OB_PARSER_ERR_NO_MEMORY;
+    ret = OB_PARSER_ERR_UNEXPECTED;
     (void)fprintf(stderr, "ERROR node%p or index:%p is NULL\n", node, index);
   } else if (NULL == source_tree) {
     // do nothing
@@ -184,7 +184,7 @@ int merge_child(ParseNode* node, void* malloc_pool, ParseNode* source_tree, int*
     do {
       ParseNode *tree = NULL;
       if (NULL == stack_top || NULL == (tree = (ParseNode *)stack_top->val_)) {
-        ret = OB_PARSER_ERR_NO_MEMORY;
+        ret = OB_PARSER_ERR_UNEXPECTED;
         (void)fprintf(stderr, "ERROR invalid null argument\n");
       } else {
         // pop stack
@@ -194,11 +194,11 @@ int merge_child(ParseNode* node, void* malloc_pool, ParseNode* source_tree, int*
         // do nothing
       } else if (T_LINK_NODE != tree->type_) {
         if (OB_UNLIKELY(*index < 0 || *index >= node->num_child_)) {
-          ret = OB_PARSER_ERR_NO_MEMORY;
+          ret = OB_PARSER_ERR_UNEXPECTED;
           (void)fprintf(
               stderr, "ERROR invalid index: %d, num_child:%d\n tree: %d", *index, node->num_child_, tree->type_);
         } else if (NULL == node->children_) {
-          ret = OB_PARSER_ERR_NO_MEMORY;
+          ret = OB_PARSER_ERR_UNEXPECTED;
           (void)fprintf(stderr, "ERROR invalid null children pointer\n");
         } else {
           node->children_[*index] = tree;
@@ -207,7 +207,7 @@ int merge_child(ParseNode* node, void* malloc_pool, ParseNode* source_tree, int*
       } else if (tree->num_child_ <= 0) {
         // do nothing
       } else if (NULL == tree->children_) {
-        ret = OB_PARSER_ERR_NO_MEMORY;
+        ret = OB_PARSER_ERR_UNEXPECTED;
         (void)fprintf(stderr, "ERROR invalid children pointer\n");
       } else {
         ParserLinkNode* tmp_node = NULL;
diff --git a/src/sql/rewrite/ob_transform_utils.cpp b/src/sql/rewrite/ob_transform_utils.cpp
index 12ef04f70f1ff6132119105b8dc2a5fcf262f8ac..c4f9dfc734d60c4b101dfa184ca4317a6c2679ee 100644
--- a/src/sql/rewrite/ob_transform_utils.cpp
+++ b/src/sql/rewrite/ob_transform_utils.cpp
@@ -256,23 +256,28 @@ int ObTransformUtils::add_new_joined_table(ObTransformerCtx* ctx, ObDMLStmt& stm
     ret = OB_ERR_UNEXPECTED;
     LOG_WARN("transform context is invalid", K(ret), K(ctx), K(stmt), K(left_table), K(right_table));
   } else {
-    JoinedTable* joined_table = static_cast<JoinedTable*>(ctx->allocator_->alloc(sizeof(JoinedTable)));
-    joined_table = new (joined_table) JoinedTable();
-    joined_table->type_ = TableItem::JOINED_TABLE;
-    joined_table->table_id_ = stmt.get_query_ctx()->available_tb_id_--;
-    joined_table->joined_type_ = join_type;
-    joined_table->left_table_ = left_table;
-    joined_table->right_table_ = right_table;
-    if (OB_FAIL(joined_table->join_conditions_.assign(joined_conds))) {
-      LOG_WARN("failed to push back join conditions", K(ret));
-    } else if (OB_FAIL(ObTransformUtils::add_joined_table_single_table_ids(*joined_table, *left_table))) {
-      LOG_WARN("failed to add left table ids", K(ret));
-    } else if (OB_FAIL(ObTransformUtils::add_joined_table_single_table_ids(*joined_table, *right_table))) {
-      LOG_WARN("failed to add right table ids", K(ret));
-    } else if (add_table && OB_FAIL(stmt.add_joined_table(joined_table))) {
-      LOG_WARN("failed to add joined table into stmt", K(ret));
+    JoinedTable *joined_table = static_cast<JoinedTable *>(ctx->allocator_->alloc(sizeof(JoinedTable)));
+    if (OB_ISNULL(joined_table)) {
+      ret = OB_ALLOCATE_MEMORY_FAILED;
+      LOG_WARN("fail to allocate memory", K(ret));
     } else {
-      new_join_table = joined_table;
+      joined_table = new (joined_table) JoinedTable();
+      joined_table->type_ = TableItem::JOINED_TABLE;
+      joined_table->table_id_ = stmt.get_query_ctx()->available_tb_id_--;
+      joined_table->joined_type_ = join_type;
+      joined_table->left_table_ = left_table;
+      joined_table->right_table_ = right_table;
+      if (OB_FAIL(joined_table->join_conditions_.assign(joined_conds))) {
+        LOG_WARN("failed to push back join conditions", K(ret));
+      } else if (OB_FAIL(ObTransformUtils::add_joined_table_single_table_ids(*joined_table, *left_table))) {
+        LOG_WARN("failed to add left table ids", K(ret));
+      } else if (OB_FAIL(ObTransformUtils::add_joined_table_single_table_ids(*joined_table, *right_table))) {
+        LOG_WARN("failed to add right table ids", K(ret));
+      } else if (add_table && OB_FAIL(stmt.add_joined_table(joined_table))) {
+        LOG_WARN("failed to add joined table into stmt", K(ret));
+      } else {
+        new_join_table = joined_table;
+      }
     }
   }
   return ret;