support json type

src/sql/engine/expr/ob_expr_json_merge.cpp

@@ -0,0 +1,40 @@
+/**
+ * Copyright (c) 2021 OceanBase
+ * OceanBase CE is licensed under Mulan PubL v2.
+ * You can use this software according to the terms and conditions of the Mulan PubL v2.
+ * You may obtain a copy of Mulan PubL v2 at:
+ *          http://license.coscl.org.cn/MulanPubL-2.0
+ * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+ * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ * See the Mulan PubL v2 for more details.
+ */
+
+// This file is for implementation of func json_merge
+#define USING_LOG_PREFIX SQL_ENG
+#include "ob_expr_json_merge.h"
+
+using namespace oceanbase::common;
+using namespace oceanbase::sql;
+
+namespace oceanbase
+{
+namespace sql
+{
+
+ObExprJsonMerge::ObExprJsonMerge(ObIAllocator &alloc)
+    : ObExprJsonMergePreserve(alloc,
+      T_FUN_SYS_JSON_MERGE,
+      N_JSON_MERGE, 
+      MORE_THAN_ONE,
+      NOT_ROW_DIMENSION)
+{
+  ;
+}
+
+ObExprJsonMerge::~ObExprJsonMerge()
+{
+}
+
+}
+}