oceanbase版本
MySQL [oceanbase]> select version();
±---------------------------+
| version() |
±---------------------------+
| 5.7.25-OceanBase-v4.2.1.10 |
±---------------------------+
1 row in set (0.00 sec)
MySQL [oceanbase]> SELECT BACKUP_SET_ID,START_TIMESTAMP,STATUS,PATH FROM DBA_OB_BACKUP_SET_FILES;
±--------------±---------------------------±--------±-----------------------------------------------------------------------------+
| BACKUP_SET_ID | START_TIMESTAMP | STATUS | PATH |
±--------------±---------------------------±--------±-----------------------------------------------------------------------------+
| 1 | 2026-08-24 17:42:31.852064 | SUCCESS | file:///backup/obcp_exam/1787534828/tenant_incarnation_1/1002/data |
| 2 | 2026-08-25 16:51:18.353416 | SUCCESS | file:///backup/obcp_exam/1787534828/tenant_incarnation_1/1002/data |
| 3 | 2026-08-26 17:00:08.951877 | SUCCESS | file:///backup/obcp_exam/1787534828/tenant_incarnation_1/1002/data |
| 4 | 2026-08-28 11:06:09.274152 | SUCCESS | file:///backup/obcp_exam/obcp_exam/1787534828/tenant_incarnation_1/1002/data |
| 5 | 2026-08-28 11:25:46.529367 | SUCCESS | file:///backup/obcp_exam/1787534828/tenant_incarnation_1/1002/data |
±--------------±---------------------------±--------±-----------------------------------------------------------------------------+
5 rows in set (0.01 sec)
情况说明，前面四个备份片已经rm -rf了，然后重新配置了备份目录、并且重新生成了backup_set_id=5的备份、
请问对于DBA_OB_BACKUP_SET_FILES视图中的前四条记录该如何删除？
还是说类似oracle的控制文件一样、超出保留时间、元数据信息会自动清理？
特别提示：目前版本是不支持手工清理的
