(USEREXIT) = OFF
目前在綜合業務系統中，設置的均是歸檔日志模式；其它系統（如事后監督、經營決策、中間業務等）一般都設置為循環日志模式。至于采用何種模式，可以通過修改數據庫配置參數（LOGRETAIN）來實現： 歸檔日志模式：db2 update db cfg for using logretain on 注：改為on后，查看數據庫配置參數logretain的值時，實際顯示的是recovery。改變此參數后，再次連接數據庫會顯示數據庫處于備份暫掛（BACKUP PENDING）狀態。這時，需要做一次對數據庫的脫機備份（db2 backup db ），才能使數據庫狀態變為正常。
循環日志模式：db2 update db cfg for using logretain on
一、修改日志模式
目的：將日志修改成為歸檔日志，才能繼續進行online備份和后面的所有試驗。
保證AUTO_DB_BACKUP = ON才能做備份。
日志格式是LOGRETAIN YES
用戶出口USEREXIT on
[db2inst1@fedora ~]$ db2 get db cfg for sample |grep LOG
Catalog cache size (4KB) (CATALOGCACHE_SZ) = (MAXAPPLS*4)
Log buffer size (4KB) (LOGBUFSZ) = 8
Log file size (4KB) (LOGFILSIZ) = 1000
Number of primary log files (LOGPRIMARY) = 3
Number of secondary log files (LOGSECOND) = 2
Changed path to log files (NEWLOGPATH) =
Path to log files = /home/db2inst1/db2inst1/NODE0000/SQL00001/SQLOGDIR/
Overflow log path (OVERFLOWLOGPATH) =
Mirror log path (MIRRORLOGPATH) =
Block log on disk full (BLK_LOG_DSK_FUL) = NO
Percent of max active log space by transaction(MAX_LOG) = 0
Num. of active log files for 1 active UOW(NUM_LOG_SPAN) = 0
Log retain for recovery enabled (LOGRETAIN) = OFF
First log archive method (LOGARCHMETH1) = OFF
Options for logarchmeth1 (LOGARCHOPT1) =
Second log archive method (LOGARCHMETH2) = OFF
Options for logarchmeth2 (LOGARCHOPT2) =
Log pages during index build (LOGINDEXBUILD) = OFF
[db2inst1@fedora ~]$
查看到
LOGRETAIN 選項為 OFF
Path to log files 選項為 /home/db2inst1/db2inst1/NODE0000/SQL00001/SQLOGDIR/
修改LOGRETAIN 選項為 ON