DB2中自动清理数据库历史文件

本篇文章主要介绍了"DB2中自动清理数据库历史文件"，主要涉及到方面的内容，对于DB2感兴趣的同学可以参考一下： DB2可以做到自动清除历史文件，有关详细介绍请参考http://www-01.ibm.com/support/knowledgecenter/SSEPGG_9....

DB2可以做到自动清除历史文件，有关详细介绍请参考

http://www-01.ibm.com/support/knowledgecenter/SSEPGG_9.7.0/com.ibm.db2.luw.admin.ha.doc/doc/t0051348.html?cp=SSEPGG_9.7.0&lang=en

这里只举一个例子：

C:\windows\system32>db2 update db cfg for sample using rec_his_retentn 1

C:\windows\system32>db2 update db cfg for sample using NUM_DB_BACKUPS 1

//重新激活数据库

C:\windows\system32>db2 list history all for db sample
                    List History File for sample
Number of matching file entries = 0

测试1.） 备份次数超过NUM_DB_BACKUPS，但时间上未达到rec_his_retentn，不会发生自动prune
C:\windows\system32>db2 "alter tablespace userspace1 rebalance"
C:\windows\system32>db2 "reorg table t1"
C:\windows\system32>db2 "backup db sample online"
Backup successful. The timestamp for this backup image is :
20151023133140
C:\windows\system32>db2 "load from t1.del of del insert into t1"
C:\windows\system32>db2 "backup db sample online"
Backup successful. The timestamp for this backup image is :
20151023133319
C:\windows\system32>db2 list history all for db sample
                    List History File for sample
Number of matching file entries = 5 <-NUM_DB_BACKUPS 达到要求, 但rec_his_retentn没有达到要求，没有prune
..

测试2.）1天之后，观察是否发生了自动prune
C:\windows\system32>db2 list history all for db sample
                    List History File for sample
Number of matching file entries = 5 <--rec_his_retentn 和 NUM_DB_BACKUPS 都达到要求, 但没有 backup 操作. 没有发生prune

测试3.）再次发出backup命令，这次的backup命令触发了之前的历史文件条目被删除
C:\windows\system32>db2 "reorg table employee"
DB20000I  The REORG command completed successfully.
C:\windows\system32>db2 backup db sample online
Backup successful. The timestamp for this backup image is :
20151024134000
C:\windows\system32>db2 list history all for db sample
                    List History File for sample
Number of matching file entries = 2  <--已经被自动prune
 Op Obj Timestamp+Sequence Type Dev Earliest Log Current Log  Backup ID
 -- --- ------------------ ---- --- ------------ ------------
--------------
  G  T  20151024133939      F       S0000530.LOG S0000530.LOG
 -----------------------------------------------------------------------
-----
  Table:  "MIAOQINGSONG"."EMPLOYEE"
 -----------------------------------------------------------------------
-----
    Comment: REORG
 Start Time: 20151024133939
   End Time: 20151024133939
     Status: A
 -----------------------------------------------------------------------
-----
  EID: 90
 Op Obj Timestamp+Sequence Type Dev Earliest Log Current Log  Backup ID
 -- --- ------------------ ---- --- ------------ ------------
--------------
  B  D  20151024134000001   N    D  S0000531.LOG S0000531.LOG
 -----------------------------------------------------------------------
-----
  Contains 3 tablespace(s):
 00001 SYSCATSPACE
 00002 USERSPACE1
 00003 SYSTOOLSPACE
 -----------------------------------------------------------------------
-----
    Comment: DB2 BACKUP SAMPLE ONLINE
 Start Time: 20151024134000
   End Time: 20151024134007
     Status: A
 -----------------------------------------------------------------------
-----
  EID: 91 Location: C:\windows\system32

以上就介绍了DB2中自动清理数据库历史文件，包括了方面的内容，希望对DB2有兴趣的朋友有所帮助。

本文网址链接：http://www.codes51.com/article/detail_323788.html