[20150717]备份变大.txt
--前几天别人系统升级，11.2.0.3升级到11.2.0.4出现备份增大的情况，我看了他升级的文档，感觉最大的可能建立了restore point。
--升级完成后没有删除。自己做一个测试。
1.建立测试环境：
SCOTT@test> @ &r/ver1
PORT_STRING VERSION BANNER
------------------------------ -------------- ----------------------------------------------------------------
x86_64/Linux 2.4.xx 10.2.0.4.0 Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bi
SCOTT@test> select FLASHBACK_ON from v$database ;
FLASHBACK_ON
------------------
NO
--建立新的表空间：
-- drop tablespace mssm including contents;
CREATE TABLESPACE MSSM DATAFILE
'/mnt/ramdisk/test/mssm01.dbf' SIZE 64M AUTOEXTEND OFF
LOGGING
ONLINE
EXTENT MANAGEMENT LOCAL AUTOALLOCATE
BLOCKSIZE 8K
SEGMENT SPACE MANAGEMENT MANUAL
FLASHBACK ON;
SCOTT@test> create table t tablespace mssm as select rownum id ,cast('testtesttesttest' as varchar2(20)) name from xmltable('1 to 100000');
Table created.
--这样建立文件大小13M。
SCOTT@test> truncate table t ;
Table truncated.
2.开始备份：
RMAN> backup datafile 6 format '/home/oracle/backup/DATAFILE6_%u' ;
$ ll -lh DATAFILE6_*
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:28:50 DATAFILE6_14qc8rii
--仅仅616K。
SCOTT@test> create restore point test0717 ;
Restore point created.
$ ll -lh DATAFILE6_*
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:28:50 DATAFILE6_14qc8rii
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:34:58 DATAFILE6_15qc8ru2
--没有变化。
SYS@test> create restore point test0717x guarantee flashback database;
create restore point test0717x guarantee flashback database
*
ERROR at line 1:
ORA-38784: Cannot create restore point 'TEST0717X'.
ORA-38787: Creating the first guaranteed restore point requires mount mode when flashback database is off.
--说明他升级在mount状态建立的guarantee flashback point。
SYS@test> shutdown immediate ;
Database closed.
Database dismounted.
ORACLE instance shut down.
SYS@test> startup mount
ORACLE instance started.
Total System Global Area 473956352 bytes
Fixed Size 2084776 bytes
Variable Size 260046936 bytes
Database Buffers 201326592 bytes
Redo Buffers 10498048 bytes
Database mounted.
SYS@test> create restore point test0717x guarantee flashback database;
Restore point created.
SYS@test> alter database open ;
Database altered.
RMAN> backup datafile 6 format '/home/oracle/backup/DATAFILE6_%u' ;
..
$ ll -lh DATAFILE6_*
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:28:50 DATAFILE6_14qc8rii
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:34:58 DATAFILE6_15qc8ru2
-rw-r----- 1 oracle oinstall 13M 2015-07-17 09:38:41 DATAFILE6_16qc8s51
--很明显备份变成了13M。建立了restore point并且属性guarantee flashback database;
SYS@test> select * from V$RESTORE_POINT;
SCN DATABASE_INCARNATION# GUA STORAGE_SIZE TIME NAME
------------ --------------------- --- ------------ ------------------------------ --------------------
12695497118 1 YES 8192000 2015-07-17 09:38:02.000000000 TEST0717X
12695496814 1 NO 0 2015-07-17 09:34:43.000000000 TEST0717
3.打开FLASHBACK_ON看看：
--10g仅仅在mount状态下打开。
SYS@test> alter database flashback on;
Database altered.
SYS@test> alter database open ;
Database altered.
$ ll -lh DATAFILE6_*
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:28:50 DATAFILE6_14qc8rii
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:34:58 DATAFILE6_15qc8ru2
-rw-r----- 1 oracle oinstall 13M 2015-07-17 09:38:41 DATAFILE6_16qc8s51
-rw-r----- 1 oracle oinstall 13M 2015-07-17 09:49:06 DATAFILE6_17qc8soi
SYS@test> drop restore point TEST0717X;
Restore point dropped.
RMAN> backup datafile 6 format '/home/oracle/backup/DATAFILE6_%u' ;
..
$ ll -lh DATAFILE6_*
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:28:50 DATAFILE6_14qc8rii
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:34:58 DATAFILE6_15qc8ru2
-rw-r----- 1 oracle oinstall 13M 2015-07-17 09:38:41 DATAFILE6_16qc8s51
-rw-r----- 1 oracle oinstall 13M 2015-07-17 09:49:06 DATAFILE6_17qc8soi
-rw-r----- 1 oracle oinstall 616K 2015-07-17 09:50:39 DATAFILE6_18qc8srf
--很明显正是建立了restore point并且属性guarantee flashback database;导致备份变大。
4.收尾还原：
SYS@test> drop restore point TEST0717;
Restore point dropped.
SYS@test> alter database flashback off;
Database altered.
RMAN> delete backupset 31,32,33,34,35;
using channel ORA_DISK_1
List of Backup Pieces
BP Key BS Key Pc# Cp# Status Device Type Piece Name
------- ------- --- --- ----------- ----------- ----------
31 31 1 1 AVAILABLE DISK /home/oracle/backup/DATAFILE6_14qc8rii
32 32 1 1 AVAILABLE DISK /home/oracle/backup/DATAFILE6_15qc8ru2
33 33 1 1 AVAILABLE DISK /home/oracle/backup/DATAFILE6_16qc8s51
34 34 1 1 AVAILABLE DISK /home/oracle/backup/DATAFILE6_17qc8soi
35 35 1 1 AVAILABLE DISK /home/oracle/backup/DATAFILE6_18qc8srf
Do you really want to delete the above objects (enter YES or NO)? yes
deleted backup piece
backup piece handle=/home/oracle/backup/DATAFILE6_14qc8rii recid=31 stamp=885288530
deleted backup piece
backup piece handle=/home/oracle/backup/DATAFILE6_15qc8ru2 recid=32 stamp=885288898
deleted backup piece
backup piece handle=/home/oracle/backup/DATAFILE6_16qc8s51 recid=33 stamp=885289121
deleted backup piece
backup piece handle=/home/oracle/backup/DATAFILE6_17qc8soi recid=34 stamp=885289746
deleted backup piece
backup piece handle=/home/oracle/backup/DATAFILE6_18qc8srf recid=35 stamp=885289839
Deleted 5 objects
--总结：
--注意这些细节，升级完成正常后删除这些restore point。