因為數據倉庫上asm的磁盤空間不足，需要刪除早期的歸檔日志，查看資料有以下兩種方式：

delete archivelog until time 'sysdate-N';

delete archivelog all completed before 'sysdate-N';

這兩個命令的差別在哪里呢？

使用list 命令來查看一下究竟...

RMAN> list archivelog until time 'sysdate-1';

using target database control file instead of recovery catalog

List of Archived Log Copies for database with db_unique_name YANGDB

=====================================================================

Key ? ? Thrd Seq ? ? S Low Time

------- ---- ------- - ---------

459 ? ? 1 ? ?463 ? ? A 08-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_463_762800109.log

460 ? ? 1 ? ?464 ? ? A 08-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_464_762800109.log

461 ? ? 1 ? ?465 ? ? A 08-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_465_762800109.log

462 ? ? 1 ? ?466 ? ? A 08-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_466_762800109.log

463 ? ? 1 ? ?467 ? ? A 09-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_467_762800109.log

464 ? ? 1 ? ?468 ? ? A 09-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_468_762800109.log

465 ? ? 1 ? ?469 ? ? A 10-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_469_762800109.log

466 ? ? 1 ? ?470 ? ? A 11-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_470_762800109.log

467 ? ? 1 ? ?471 ? ? A 11-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_471_762800109.log

468 ? ? 1 ? ?472 ? ? A 12-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_472_762800109.log

469 ? ? 1 ? ?473 ? ? A 13-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_473_762800109.log

470 ? ? 1 ? ?474 ? ? A 13-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_474_762800109.log

471 ? ? 1 ? ?475 ? ? A 14-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_475_762800109.log

472 ? ? 1 ? 476? ? A 15-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_476_762800109.log

歸檔日志的序列號碼到476

RMAN> list archivelog all completed before 'sysdate-1';

List of Archived Log Copies for database with db_unique_name YANGDB

=====================================================================

Key ? ? Thrd Seq ? ? S Low Time

------- ---- ------- - ---------

459 ? ? 1 ? ?463 ? ? A 08-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_463_762800109.log

460 ? ? 1 ? ?464 ? ? A 08-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_464_762800109.log

461 ? ? 1 ? ?465 ? ? A 08-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_465_762800109.log

462 ? ? 1 ? ?466 ? ? A 08-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_466_762800109.log

463 ? ? 1 ? ?467 ? ? A 09-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_467_762800109.log

464 ? ? 1 ? ?468 ? ? A 09-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_468_762800109.log

465 ? ? 1 ? ?469 ? ? A 10-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_469_762800109.log

466 ? ? 1 ? ?470 ? ? A 11-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_470_762800109.log

467 ? ? 1 ? ?471 ? ? A 11-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_471_762800109.log

468 ? ? 1 ? ?472 ? ? A 12-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_472_762800109.log

469 ? ? 1 ? ?473 ? ? A 13-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_473_762800109.log

470 ? ? 1 ? ?474 ? ? A 13-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_474_762800109.log

471 ? ? 1 ? 475? ? A 14-JAN-12 Name: /opt/oracle/yangdb_arch/yangdb_1_475_762800109.log

歸檔日志的序列號碼到475

查看v$archived_log 視圖從中獲取 時間和序列號信息！

SYS@yangdb> select THREAD#,sequence#,FIRST_TIME,COMPLETION_TIME

2 ? from v$archived_log order by thread#,sequence#;

THREAD# SEQUENCE# FIRST_TIME ? ? ?COMPLETION_TIME

------- ---------- -------------- -------------------

1 ? ? ? ?470 ?2012-01-11 11:00:10 ?2012-01-11 22:08:23

1 ? ? ? ?471 ?2012-01-11 22:08:20 ?2012-01-12 17:00:10

1 ? ? ? ?472 ?2012-01-12 17:00:10 ?2012-01-13 02:00:28

1 ? ? ? ?473 ?2012-01-13 02:00:28 ?2012-01-13 22:09:56

1 ? ? ? ?474 ?2012-01-13 22:09:55 ?2012-01-14 22:01:02

14752012-01-14 22:01:022012-01-15 06:46:14==list archivelog all completed 以COMPLETION_TIME為基準

1476 ?2012-01-15 06:46:142012-01-30 14:10:18 ==list archivelog until 以FIRST_TIME 為基準 編號476的日志橫跨15號和30號兩天，以first_time的值來截取！

1 ? ? ? ?477 ?2012-01-30 14:10:15 ?2012-01-30 14:10:23

1 ? ? ? ?478 ?2012-01-30 14:10:22 ?2012-01-30 14:10:29

1 ? ? ? ?479 ?2012-01-30 14:10:28 ?2012-01-30 14:10:33

1 ? ? ? ?480 ?2012-01-30 14:10:32 ?2012-01-30 14:10:40

總結：

delete archivelog until time 'sysdate-N';

該命令刪除日志時的時間基準是first_name

delete archivelog all completed before 'sysdate-N';

該命令刪除日志時的時間基準是completion_time