Fix outerjoin on condition pushdown parent_namespace_stmt issue

src/sql/rewrite/ob_transform_simplify.cpp

@@ -356,8 +356,9 @@ int ObTransformSimplify::push_down_on_condition(ObDMLStmt *stmt,
     LOG_WARN("failed to update column item rel id", K(ret));
   }
 
-  if (OB_FAIL(ret)) {
-  } else if (OB_FAIL(child_stmt->adjust_subquery_stmt_parent(stmt, child_stmt))) {
+  if (OB_SUCC(ret)) {
+    child_stmt->set_parent_namespace_stmt(stmt->get_parent_namespace_stmt());
+    if (OB_FAIL(child_stmt->adjust_subquery_stmt_parent(stmt, child_stmt))) {
       LOG_WARN("failed to adjust subquery stmt parent", K(ret));
     } else if (OB_FAIL(stmt->get_column_exprs(join_table->right_table_->table_id_, old_column_exprs))) {
       LOG_WARN("failed to get column exprs", K(ret));
@@ -369,6 +370,7 @@ int ObTransformSimplify::push_down_on_condition(ObDMLStmt *stmt,
     } else if (OB_FAIL(stmt->formalize_stmt(ctx_->session_info_))) {
       LOG_WARN("failed to formalize stmt", K(ret));
     }
+  }
   return ret;
 }