oracle RMAN備份FORMAT格式中%a是什麼意思

今天三思問我一個問題：RMAN備份FORMAT格式中%a的含義。

其實Oracle的文檔有這個表述：

%a

Specifies the activation ID of the database.

不過這個描述很不明確。其實junsansi的意思是，這個%a對應的資訊在資料庫中的哪裡體現出來。

下面先看看備份資訊裡面的這個值：

[oracle@yans1 ~]$ rman target /

Recovery Manager: Release10.2.0.3.0 - Production on星期四7月16 14:18:14 2009

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

connected to target database: TEST08 (DBID=3812548755)

RMAN> backup tablespace users format '/data/backup/test08_%a';

Starting backup at 16-7月-09

using target database control file instead of recovery catalog

allocated channel: ORA_DISK_1

channel ORA_DISK_1: sid=100 devtype=DISK

channel ORA_DISK_1: starting full datafile backupset

channel ORA_DISK_1: specifying datafile(s) in backupset

RMAN-00571: ===========================================================

RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============

RMAN-00571: ===========================================================

RMAN-03009: failure of backup command on ORA_DISK_1 channel at 07/16/2009 14:18:38

ORA-19602: cannot backup or copy active file in NOARCHIVELOG mode

RMAN> sql 'alter tablespace users read only';

sql statement: alter tablespace users read only

RMAN> backup tablespace users format '/data/backup/test08_%a';

Starting backup at 16-7月-09

using channel ORA_DISK_1

channel ORA_DISK_1: starting full datafile backupset

channel ORA_DISK_1: specifying datafile(s) in backupset

input datafile fno=00004 name=/data/oradata/test08/users01.dbf

channel ORA_DISK_1: starting piece 1 at 16-7月-09

channel ORA_DISK_1: finished piece 1 at 16-7月-09

piece handle=/data/backup/test08_657125523 tag=TAG20090716T141924 comment=NONE

channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01

Finished backup at 16-7月-09

RMAN> exit

Recovery Manager complete.

可以看到，對應的activation的ID是657125523。

而且根據文檔的描述，這個屬性是資料庫的，但是在V$DATABASE視圖中找不到這個對應的值。

SQL> SELECT VIEW_DEFINITION FROM V$FIXED_VIEW_DEFINITION

2  WHERE VIEW_NAME = 'GV$DATABASE';

VIEW_DEFINITION

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

select di.inst_id,di.didbi,di.didbn,to_date(di.dicts,'MM/DD/RR HH24:MI:SS','NLS_CALENDAR=Gregorian'),to_number(di.dirls)

,to_date(di.dirlc,'MM/DD/RR HH24:MI:SS','NLS_CALENDAR=Gregorian'),to_number(di.diprs),to_date(di.diprc,'MM/DD/RR HH24:MI

:SS','NLS_CALENDAR=Gregorian'),decode(di.dimla,0,'NOARCHIVELOG',1,'ARCHIVELOG','MANUAL'),to_number(di.discn),to_number(d

i.difas),decode(bitand(di.diflg,256),256,'CREATED',decode(bitand(di.diflg,1024),1024,'STANDBY',decode(bitand(di.diflg,32

768),32768,'CLONE',decode(bitand(di.diflg,4096),4096,'BACKUP','CURRENT')))),to_date(di.dicct,'MM/DD/RR HH24:MI:SS','NLS_

CALENDAR=Gregorian'),di.dicsq,to_number(di.dickp_scn),to_date(di.dickp_tim,'MM/DD/RR HH24:MI:SS','NLS_CALENDAR=Gregorian

'),decode(bitand(di.diflg,4),4,'REQUIRED',decode(di.diirs,0,'NOT ALLOWED','ALLOWED')),to_date(di.divts,'MM/DD/RR HH24:MI

:SS','NLS_CALENDAR=Gregorian'),decode(di.didor,0,'MOUNTED',decode(di.didor,1,'READ WRITE','READ ONLY')),decode(bitand(di

.diflg,65536),65536,'MAXIMUM PROTECTION',decode(bitand(di.diflg,128),128,'MAXIMUM AVAILABILITY',decode(bitand(di.diflg,1

34217728),134217728,'RESYNCHRONIZATION',decode(bitand(di.diflg,8),8,'UNPROTECTED','MAXIMUM PERFORMANCE')))),decode(di.di

prt,1,'MAXIMUM PROTECTION',2,'MAXIMUM AVAILABILITY',3,'RESYNCHRONIZATION',4,'MAXIMUM PERFORMANCE',5,'UNPROTECTED',  'UNK

NOWN'),decode(di.dirae,0,'DISABLED',1,'SEND',2,'RECEIVE',3,'ENABLED','UNKNOWN'),to_number(di.diacid),to_number(di.diacid

),decode(bitand(di.diflg,33554432),33554432,'LOGICAL STANDBY',decode(bitand(di.diflg,1024),1024,'PHYSICAL STANDBY','PRIM

ARY')),to_number(di.diars),decode(bitand(difl2,1),1,'ENABLED','DISABLED'),decode(di.disos,0,'IMPOSSIBLE',1,'NOT ALLOWED'

,2,'SWITCHOVER LATENT',3,'SWITCHOVER PENDING',4,'TO PRIMARY',5,'TO STANDBY',6,'RECOVERY NEEDED',7,'SESSIONS ACTIVE',8,'P

REPARING SWITCHOVER',9,'PREPARING DICTIONARY',10,'TO LOGICAL STANDBY','UNKNOWN'),decode(di.didgd,0,'DISABLED','ENABLED')

本文URL地址：http://www.bianceng.cn/database/Oracle/201410/45461.htm