Oracle RMAN 清除归档日志

在开发环境及UAT环境经常碰到需要清除归档日志的情形，对于这个问题方法有很多。可以直接使用rm方式清除归档日志，也可以使用find命令来查找符合条件的记录来清除归档日志，或者直接写个shell脚本来搞定。这样在DEV或者UAT还可以，但是在Prod环境还是建议使用RMAN提供的命令来搞定比较妥当。因为rm，find方式删除了实际的归档日志也释放了空间，但对应的存储在控制文件中的归档信息并没有彻底清除。依旧占用着一些空间未能及时清除而需要控制文件通过age out方式来释放空间。本文描述了使用RMAN方式来清除归档日志，同时也可以将其部署到shell脚本中使用。

有关阅读本文需要的相关参考

1、清除归档日志的方式

a、手动删除

使用rm 或者find方式来删除，通过该方式删除之后，在RMAN下可以通过 crosscheck archivelog all 校验归档是否失效，如下面的操作:

rm -rf arch_816906485_1_10.arc

find /u02/database/GOBO1/archive/ -ctime +0 -delete

RMAN> crosscheck archivelog all

b、使用RMAN方式清除

RMAN清除方式会自动清除磁盘上的归档日志文件，同时会释放控制文件中对应的归档日志的归档信息。

可以基于不同的条件来清除归档日志，如基于SCN，基于SEQUENCE，基于TIME等方式。

对于上述的三种方式又可以配合from, until, between .. and .. 等等子句来限定范围，方式灵活多变。

下面的命令用于校验归档日志的有效性，列出无效的归档日志，以及以何种方式清除归档日志，列出几种常用的:

crosscheck archivelog all;                            --->校验日志的可用性

list expired archivelog all;                          --->列出所有失效的归档日志

delete archivelog until sequence 16;                  --->删除log sequence为16及16之前的所有归档日志

delete archivelog all completed before 'sysdate-7';    --->删除系统时间7天以前的归档日志，不会删除闪回区有效的归档日志

delete archivelog all completed before 'sysdate - 1';  --->同上，1天以前的

delete archivelog from time 'sysdate-1';              --->注意这个命令，删除系统时间1天以内到现在的归档日志

delete noprompt archivelog all completed before 'sysdate';  --->该命令清除所有的归档日志

delete noprompt archivelog all;                              --->同上一命令

2、演练使用RMAN清除归档日志

robin@SZDB:~> export ORACLE_SID=GOBO1
robin@SZDB:~> rman target /

Recovery Manager: Release 10.2.0.3.0 - Production on Thu Jul 11 17:07:00 2013

Copyright (c) 1982, 2005, Oracle.  All rights reserved.

connected to target database: GOBO1 (DBID=733951103)

RMAN> host;

robin@SZDB:~> cd /u02/database/GOBO1/archive/
robin@SZDB:/u02/database/GOBO1/archive> ls     
arch_816906485_1_10.arc      arch_816906485_1_12.arc 
arch_816906485_1_11.arc      arch_816906485_1_13.arc 
    ............

robin@SZDB:/u02/database/GOBO1/archive> rm -rf arch_816906485_1_10.arc arch_816906485_1_11.arc arch_816906485_1_12.arc
robin@SZDB:/u02/database/GOBO1/archive> exit;
exit                                       
host command complete                       
                                           
RMAN> crosscheck archivelog all;               
released channel: ORA_DISK_1                                                                     
allocated channel: ORA_DISK_1                                                                     
channel ORA_DISK_1: sid=1075 devtype=DISK                                                         
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_9.arc recid=2085 stamp=817211151
validation failed for archived log                                                               
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_10.arc recid=2086 stamp=817250793
      ..............
validation succeeded for archived log                                                             
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_90.arc recid=2166 stamp=820458049
Crosschecked 83 objects                   

RMAN> list expired archivelog all;

List of Archived Log Copies
Key    Thrd Seq    S Low Time          Name
------- ---- ------- - ----------------- ----
2086    1    10      X 20130604 11:05:51 /u02/database/GOBO1/archive/arch_816906485_1_10.arc
2087    1    11      X 20130604 22:06:17 /u02/database/GOBO1/archive/arch_816906485_1_11.arc
2088    1    12      X 20130605 19:30:53 /u02/database/GOBO1/archive/arch_816906485_1_12.arc

RMAN> delete archivelog until sequence 16;

released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=1075 devtype=DISK

List of Archived Log Copies
Key    Thrd Seq    S Low Time          Name
------- ---- ------- - ----------------- ----
2084    1    8      A 20130604 09:53:17 /u02/database/GOBO1/archive/arch_816906485_1_8.arc
                        .................
2092    1    16      A 20130607 22:03:23 /u02/database/GOBO1/archive/arch_816906485_1_16.arc

Do you really want to delete the above objects (enter YES or NO)? yes
          ...............
deleted archive log
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_16.arc recid=2092 stamp=817516861
Deleted 9 objects

RMAN> delete archivelog all completed before 'sysdate-7';

released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=1075 devtype=DISK

List of Archived Log Copies
Key    Thrd Seq    S Low Time          Name
------- ---- ------- - ----------------- ----
2093    1    17      A 20130608 00:01:00 /u02/database/GOBO1/archive/arch_816906485_1_17.arc
2094    1    18      A 20130608 18:00:17 /u02/database/GOBO1/archive/arch_816906485_1_18.arc
            ...........
deleted archive log
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_72.arc recid=2148 stamp=819847035
Deleted 56 objects           

RMAN> list copy of database archivelog all;

List of Archived Log Copies
Key    Thrd Seq    S Low Time          Name
------- ---- ------- - ----------------- ----
2149    1    73      A 20130703 23:17:13 /u02/database/GOBO1/archive/arch_816906485_1_73.arc
2150    1    74      A 20130704 22:00:19 /u02/database/GOBO1/archive/arch_816906485_1_74.arc
2151    1    75      A 20130704 22:04:40 /u02/database/GOBO1/archive/arch_816906485_1_75.arc
                      ...............
2164    1    88      A 20130709 23:19:34 /u02/database/GOBO1/archive/arch_816906485_1_88.arc
2165    1    89      A 20130710 13:00:34 /u02/database/GOBO1/archive/arch_816906485_1_89.arc
2166    1    90      A 20130710 22:02:44 /u02/database/GOBO1/archive/arch_816906485_1_90.arc

RMAN> delete archivelog from time 'sysdate-1';

released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=1075 devtype=DISK

List of Archived Log Copies
Key    Thrd Seq    S Low Time          Name
------- ---- ------- - ----------------- ----
2165    1    89      A 20130710 13:00:34 /u02/database/GOBO1/archive/arch_816906485_1_89.arc
2166    1    90      A 20130710 22:02:44 /u02/database/GOBO1/archive/arch_816906485_1_90.arc

Do you really want to delete the above objects (enter YES or NO)? yes
deleted archive log
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_89.arc recid=2165 stamp=820447373
deleted archive log
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_90.arc recid=2166 stamp=820458049
Deleted 2 objects

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

released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=1075 devtype=DISK

List of Archived Log Copies
Key    Thrd Seq    S Low Time          Name
------- ---- ------- - ----------------- ----
2149    1    73      A 20130703 23:17:13 /u02/database/GOBO1/archive/arch_816906485_1_73.arc
              .......................
2164    1    88      A 20130709 23:19:34 /u02/database/GOBO1/archive/arch_816906485_1_88.arc

Do you really want to delete the above objects (enter YES or NO)? yes
    ................
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_88.arc recid=2164 stamp=820414835
Deleted 16 objects

RMAN> sql " alter system archive log current";

sql statement:  alter system archive log current

RMAN> list copy of archivelog all;

List of Archived Log Copies
Key    Thrd Seq    S Low Time          Name
------- ---- ------- - ----------------- ----
2167    1    91      A 20130711 01:00:48 /u02/database/GOBO1/archive/arch_816906485_1_91.arc

RMAN> delete noprompt archivelog all completed before 'sysdate';

released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=1075 devtype=DISK

List of Archived Log Copies
Key    Thrd Seq    S Low Time          Name
------- ---- ------- - ----------------- ----
2167    1    91      A 20130711 01:00:48 /u02/database/GOBO1/archive/arch_816906485_1_91.arc
deleted archive log
archive log filename=/u02/database/GOBO1/archive/arch_816906485_1_91.arc recid=2167 stamp=820517964
Deleted 1 objects