[FEAT MERGE] Implement tenant cloning mechanism

Co-authored-by: wanyue-wy <345657357@qq.com>

src/sql/engine/cmd/ob_tenant_snapshot_executor.h

@@ -0,0 +1,56 @@
+/**
+ * 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.
+ */
+
+#ifndef __OB_SQL_TENANT_SNAPSHOT_EXECUTOR_H__
+#define __OB_SQL_TENANT_SNAPSHOT_EXECUTOR_H__
+
+#include "sql/engine/ob_exec_context.h"
+
+namespace oceanbase
+{
+namespace share
+{
+class ObTenantSnapshotID;
+}
+
+namespace sql
+{
+class ObCreateTenantSnapshotStmt;
+class ObDropTenantSnapshotStmt;
+
+class ObCreateTenantSnapshotExecutor
+{
+public:
+  ObCreateTenantSnapshotExecutor() {}
+  virtual ~ObCreateTenantSnapshotExecutor() {}
+  int execute(ObExecContext &ctx, ObCreateTenantSnapshotStmt &stmt);
+private:
+  int wait_create_finish_(const uint64_t tenant_id,
+                          const share::ObTenantSnapshotID &tenant_snapshot_id,
+                          ObExecContext &ctx);
+  DISALLOW_COPY_AND_ASSIGN(ObCreateTenantSnapshotExecutor);
+};
+
+class ObDropTenantSnapshotExecutor
+{
+public:
+  ObDropTenantSnapshotExecutor() {}
+  virtual ~ObDropTenantSnapshotExecutor() {}
+  int execute(ObExecContext &ctx, ObDropTenantSnapshotStmt &stmt);
+private:
+  DISALLOW_COPY_AND_ASSIGN(ObDropTenantSnapshotExecutor);
+};
+
+} //end namespace sql
+} //end namespace oceanbase
+
+#endif //__OB_SQL_TENANT_SNAPSHOT_EXECUTOR_H__