Oracle rman备份保留策略,归档删除策略及delete命令的使用

本文涉及的产品
日志服务 SLS,月写入数据量 50GB 1个月
简介: oracle rman备份保留策略、归档策略的使用及对delete命令的影响

今日学习Oracle rman备份保留策略,归档删除策略,发现delete obsolete命令不考虑归档删除策略,只遵从备份保留策略,delete archive log 只遵从归档删除策略,不考虑备份保留策略,实验验证一下。

1 数据库环境
1.1 数据库版本
SQL> select * from v$version;

BANNER

Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
PL/SQL Release 11.2.0.4.0 - Production
CORE 11.2.0.4.0 Production
TNS for Linux: Version 11.2.0.4.0 - Production
NLSRTL Version 11.2.0.4.0 - Production
1.2 数据库日志模式
SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 1
Next log sequence to archive 3
Current log sequence 3

1.3 rman参数配置
RMAN> show all;

using target database control file instead of recovery catalog
RMAN configuration parameters for database with db_unique_name ORCL11G are:
CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default
CONFIGURE BACKUP OPTIMIZATION OFF; # default
CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default
CONFIGURE CONTROLFILE AUTOBACKUP OFF; # default
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default
CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default
CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE MAXSETSIZE TO UNLIMITED; # default
CONFIGURE ENCRYPTION FOR DATABASE OFF; # default
CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default
CONFIGURE COMPRESSION ALGORITHM 'BASIC' AS OF RELEASE 'DEFAULT' OPTIMIZE FOR LOAD TRUE ; # default
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default
CONFIGURE SNAPSHOT CONTROLFILE NAME TO '/u01/app/oracle/product/11.2.0/db_1/dbs/snapcf_orcl11g.f'; # default
2 设置备份保留策略及归档删除策略
2.1 保留策略采用默认设置,保留一个有效备份。
2.2 设置归档删除策略为备份到磁盘设备两次
RMAN> configure archivelog deletion policy to backed up 2 times to device type disk;

old RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP 1 TIMES TO DISK;
new RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP 2 TIMES TO DISK;
new RMAN configuration parameters are successfully stored

3 验证delete obsolete命令
3.1 备份归档日志
RMAN> backup archivelog all;
3.2 检查以下废弃的备份及文件
RMAN> report obsolete;

RMAN retention policy will be applied to the command
RMAN retention policy is set to redundancy 1
Report of obsolete backups and copies
Type Key Completion Time Filename/Handle


Backup Set 1 03-AUG-19
Backup Piece 1 03-AUG-19 /home/oracle/backup/c_ORCL11G_20190803_1
Backup Set 2 03-AUG-19
Backup Piece 2 03-AUG-19 /home/oracle/backup/ctl_04u899pu_20190803_4;

上面两个备份时以前的控制文件备份

3.3 切换日志,产生几个归档
RMAN> sql 'alter system switch logfile';

sql statement: alter system switch logfile
3.4 做一个数据库全备
RMAN> back up database;
3.5 检查以下废弃的文件
RMAN> report obsolete;

RMAN retention policy will be applied to the command
RMAN retention policy is set to redundancy 1
Report of obsolete backups and copies
Type Key Completion Time Filename/Handle


Archive Log 3 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_5_gl9cvbtm_.arc
Archive Log 1 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_8_gmqbfowj_.arc
Archive Log 2 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_9_gmqbjrmd_.arc
Archive Log 5 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_7_gl9df4p5_.arc
Archive Log 6 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_4_gl9clfkz_.arc
Archive Log 4 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_6_gl9cxkm7_.arc
Archive Log 7 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_10_gmqgf8cl_.arc
Archive Log 8 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_8_gmqgf8jr_.arc
Archive Log 9 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_9_gmqgf905_.arc
Backup Set 1 03-AUG-19
Backup Piece 1 03-AUG-19 /home/oracle/backup/c_ORCL11G_20190803_1
Backup Set 2 03-AUG-19
Backup Piece 2 03-AUG-19 /home/oracle/backup/ctl_04u899pu_20190803_4;
Archive Log 13 03-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_03/o1_mf_1_1_gnb29x1t_.arc
Backup Set 3 03-AUG-19
Backup Piece 3 03-AUG-19 /home/oracle/backup/c_ORCL11G_%l_20190803_6
Archive Log 14 04-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_04/o1_mf_1_1_gnfccmyr_.arc
Archive Log 15 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_2_gnvx3c6q_.arc
Archive Log 16 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_3_gnvxwrj5_.arc
Backup Set 4 10-AUG-19
Backup Piece 4 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxws3s_.bkp
Backup Set 5 10-AUG-19
Backup Piece 5 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxwt66_.bkp
Archive Log 17 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_4_gnvy7rm9_.arc
Backup Set 6 10-AUG-19
Backup Piece 6 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxwv8t_.bkp
Archive Log 18 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_5_gnvy9x45_.arc
Archive Log 19 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_6_gnvyb315_.arc

从输出来看,数据库全备之前产生的归档日志及其备份都被标识为废弃文件

3.6 删除废弃的文件
RMAN> delete noprompt obsolete;

RMAN retention policy will be applied to the command
RMAN retention policy is set to redundancy 1
using channel ORA_DISK_1
Deleting the following obsolete backups and copies:
Type Key Completion Time Filename/Handle


Archive Log 3 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_5_gl9cvbtm_.arc
Archive Log 1 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_8_gmqbfowj_.arc
Archive Log 2 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_9_gmqbjrmd_.arc
Archive Log 5 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_7_gl9df4p5_.arc
Archive Log 6 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_4_gl9clfkz_.arc
Archive Log 4 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_6_gl9cxkm7_.arc
Archive Log 7 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_10_gmqgf8cl_.arc
Archive Log 8 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_8_gmqgf8jr_.arc
Archive Log 9 27-JUL-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_9_gmqgf905_.arc
Backup Set 1 03-AUG-19
Backup Piece 1 03-AUG-19 /home/oracle/backup/c_ORCL11G_20190803_1
Backup Set 2 03-AUG-19
Backup Piece 2 03-AUG-19 /home/oracle/backup/ctl_04u899pu_20190803_4;
Archive Log 13 03-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_03/o1_mf_1_1_gnb29x1t_.arc
Backup Set 3 03-AUG-19
Backup Piece 3 03-AUG-19 /home/oracle/backup/c_ORCL11G_%l_20190803_6
Archive Log 14 04-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_04/o1_mf_1_1_gnfccmyr_.arc
Archive Log 15 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_2_gnvx3c6q_.arc
Archive Log 16 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_3_gnvxwrj5_.arc
Backup Set 4 10-AUG-19
Backup Piece 4 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxws3s_.bkp
Backup Set 5 10-AUG-19
Backup Piece 5 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxwt66_.bkp
Archive Log 17 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_4_gnvy7rm9_.arc
Backup Set 6 10-AUG-19
Backup Piece 6 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxwv8t_.bkp
Archive Log 18 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_5_gnvy9x45_.arc
Archive Log 19 10-AUG-19 /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_6_gnvyb315_.arc
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_5_gl9cvbtm_.arc RECID=3 STAMP=1014719046
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_8_gmqbfowj_.arc RECID=1 STAMP=1014719046
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_9_gmqbjrmd_.arc RECID=2 STAMP=1014719046
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_7_gl9df4p5_.arc RECID=5 STAMP=1014719047
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_4_gl9clfkz_.arc RECID=6 STAMP=1014719047
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_09/o1_mf_1_6_gl9cxkm7_.arc RECID=4 STAMP=1014719047
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_10_gmqgf8cl_.arc RECID=7 STAMP=1014720040
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_8_gmqgf8jr_.arc RECID=8 STAMP=1014720040
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_07_27/o1_mf_1_9_gmqgf905_.arc RECID=9 STAMP=1014720041
deleted backup piece
backup piece handle=/home/oracle/backup/c_ORCL11G_20190803_1 RECID=1 STAMP=1015326317
deleted backup piece
backup piece handle=/home/oracle/backup/ctl_04u899pu_20190803_4; RECID=2 STAMP=1015326527
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_03/o1_mf_1_1_gnb29x1t_.arc RECID=13 STAMP=1015330237
deleted backup piece
backup piece handle=/home/oracle/backup/c_ORCL11G_%l_20190803_6 RECID=3 STAMP=1015326746
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_04/o1_mf_1_1_gnfccmyr_.arc RECID=14 STAMP=1015437812
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_2_gnvx3c6q_.arc RECID=15 STAMP=1015914731
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_3_gnvxwrj5_.arc RECID=16 STAMP=1015915544
deleted backup piece
backup piece handle=/u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxws3s_.bkp RECID=4 STAMP=1015915545
deleted backup piece
backup piece handle=/u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxwt66_.bkp RECID=5 STAMP=1015915546
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_4_gnvy7rm9_.arc RECID=17 STAMP=1015915896
deleted backup piece
backup piece handle=/u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_annnn_TAG20190810T064544_gnvxwv8t_.bkp RECID=6 STAMP=1015915547
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_5_gnvy9x45_.arc RECID=18 STAMP=1015915965
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_6_gnvyb315_.arc RECID=19 STAMP=1015915971
Deleted 22 objects
数据库备份之前产生的备份集及归档日志都被删除了,检查以下现有备份文件及归档日志,没有归档日志,备份集只剩一下数据库全备的:

RMAN> list backup;

List of Backup Sets

BS Key Type LV Size Device Type Elapsed Time Completion Time


7 Full 1.03G DISK 00:00:27 10-AUG-19

    BP Key: 7   Status: AVAILABLE  Compressed: NO  Tag: TAG20190810T065316
    Piece Name: /u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_nnndf_TAG20190810T065316_gnvybw9j_.bkp

List of Datafiles in backup set 7
File LV Type Ckp SCN Ckp Time Name
---- -- ---- ---------- --------- ----
1 Full 1028593 10-AUG-19 /u01/app/oracle/oradata/orcl11g/system01.dbf
2 Full 1028593 10-AUG-19 /u01/app/oracle/oradata/orcl11g/sysaux01.dbf
3 Full 1028593 10-AUG-19 /u01/app/oracle/oradata/orcl11g/undotbs01.dbf
4 Full 1028593 10-AUG-19 /u01/app/oracle/oradata/orcl11g/users01.dbf

BS Key Type LV Size Device Type Elapsed Time Completion Time


8 Full 9.67M DISK 00:00:01 10-AUG-19

    BP Key: 8   Status: AVAILABLE  Compressed: NO  Tag: TAG20190810T065316
    Piece Name: /u01/app/oracle/fast_recovery_area/ORCL11G/backupset/2019_08_10/o1_mf_ncsnf_TAG20190810T065316_gnvyd0dg_.bkp

SPFILE Included: Modification time: 10-AUG-19
SPFILE db_unique_name: ORCL11G
Control File Included: Ckp SCN: 1028605 Ckp time: 10-AUG-19
RMAN> list archivelog all;

specification does not match any archived log in the repository

4 验证delete archivelog命令
4.1 更改归档删除策略为None,归档删除策略为未经备份的归档日志也可以删除。
RMAN> CONFIGURE ARCHIVELOG DELETION POLICY TO None;

old RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP 2 TIMES TO DISK;
new RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE;
new RMAN configuration parameters are successfully stored

4.2 产生几个归档日志
RMAN> sql 'alter system switch logfile';

sql statement: alter system switch logfile

RMAN> sql 'alter system switch logfile';

sql statement: alter system switch logfile

RMAN> sql 'alter system switch logfile';

sql statement: alter system switch logfile

RMAN>
RMAN> list archivelog all;

List of Archived Log Copies for database with db_unique_name ORCL11G

Key Thrd Seq S Low Time


20 1 7 A 10-AUG-19

    Name: /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_7_gnvzpxgh_.arc

21 1 8 A 10-AUG-19

    Name: /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_8_gnvzq4ch_.arc

22 1 9 A 10-AUG-19

    Name: /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_9_gnvzq9jc_.arc

4.3 系统中没有obsolete文件
RMAN> report obsolete;

RMAN retention policy will be applied to the command
RMAN retention policy is set to redundancy 1
no obsolete backups found

4.4 删除归档日志
RMAN> delete noprompt archivelog all;

released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=1 device type=DISK

List of Archived Log Copies for database with db_unique_name ORCL11G

Key Thrd Seq S Low Time


20 1 7 A 10-AUG-19

    Name: /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_7_gnvzpxgh_.arc

21 1 8 A 10-AUG-19

    Name: /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_8_gnvzq4ch_.arc

22 1 9 A 10-AUG-19

    Name: /u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_9_gnvzq9jc_.arc

deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_7_gnvzpxgh_.arc RECID=20 STAMP=1015917405
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_8_gnvzq4ch_.arc RECID=21 STAMP=1015917412
deleted archived log
archived log file name=/u01/app/oracle/fast_recovery_area/ORCL11G/archivelog/2019_08_10/o1_mf_1_9_gnvzq9jc_.arc RECID=22 STAMP=1015917417
Deleted 3 objects

RMAN>

删除了刚才产生的归档日志,这些归档日志是当前备份保留策略所需要的,也没有备份。可见,delete archivelog命令并不考虑数据库备份策略。

5 结论
从上面的实验上来看,delete archivelog命令只遵循归档日志删除策略,delete obsolete命令只遵循备份保留策略,因此,在使用时要注意二者的相互影响,即delete obsolete 命令可以破坏归档日志删除策略,delete archivelog 可以破坏备份保留策略,在使用脚本自动备份时,要仔细分析和验证,避免造成意外的结果,而在dataguard环境尤其要谨慎使用delete obsolete 命令,避免删除未传输的日志。

相关实践学习
日志服务之使用Nginx模式采集日志
本文介绍如何通过日志服务控制台创建Nginx模式的Logtail配置快速采集Nginx日志并进行多维度分析。
相关文章
|
1月前
|
SQL Oracle 关系型数据库
【赵渝强老师】Oracle的控制文件与归档日志文件
本文介绍了Oracle数据库中的控制文件和归档日志文件。控制文件记录了数据库的物理结构信息,如数据库名、数据文件和联机日志文件的位置等。为了保护数据库,通常会进行控制文件的多路复用。归档日志文件是联机重做日志文件的副本,用于记录数据库的变更历史。文章还提供了相关SQL语句,帮助查看和设置数据库的日志模式。
【赵渝强老师】Oracle的控制文件与归档日志文件
|
1月前
|
存储 Oracle 关系型数据库
Oracle数据库优化策略
【10月更文挑战第25天】Oracle数据库优化策略
31 5
|
4月前
|
运维 Oracle 前端开发
Oracle 11g RAC集群日常运维命令总结
Oracle 11g RAC集群日常运维命令总结
112 2
|
4月前
|
SQL 运维 Oracle
入门级Oracle 11g日常运维命令总结
入门级Oracle 11g日常运维命令总结
176 1
|
4月前
|
SQL Oracle 关系型数据库
"揭秘!一键解锁Oracle日志清理魔法,让海量归档日志无处遁形,守护数据库健康,告别磁盘空间告急噩梦!"
【8月更文挑战第9天】随着Oracle数据库在企业应用中的普及,归档日志管理对保持数据库健康至关重要。归档日志记录所有更改,对数据恢复极为重要,但也可能迅速占用大量磁盘空间影响性能。利用Oracle提供的RMAN工具,可通过编写Shell脚本来自动清理归档日志。脚本包括设置环境变量、连接数据库、检查和删除指定时间前的日志,并记录执行情况。通过Cron作业定时运行脚本,可有效管理日志文件,确保数据库稳定运行。
124 7
|
4月前
|
监控 Oracle 关系型数据库
"深度剖析:Oracle SGA大小调整策略——从组件解析到动态优化,打造高效数据库性能"
【8月更文挑战第9天】在Oracle数据库性能优化中,系统全局区(SGA)的大小调整至关重要。SGA作为一组共享内存区域,直接影响数据库处理能力和响应速度。本文通过问答形式介绍SGA调整策略:包括SGA的组成(如数据缓冲区、共享池等),如何根据负载与物理内存确定初始大小,手动调整SGA的方法(如使用`ALTER SYSTEM`命令),以及利用自动内存管理(AMM)特性实现智能调整。调整过程中需注意监控与测试,确保稳定性和性能。
392 2
|
5月前
|
Oracle 安全 关系型数据库
|
5月前
|
存储 Oracle 关系型数据库
|
5月前
|
Oracle 关系型数据库 数据库
|
5月前
|
存储 Oracle 关系型数据库
关系型数据库Oracle运行RMAN脚本
【7月更文挑战第23天】
56 4