关于redo log的修改与重建
有时随着业务的发展需要对redo log日志进行重新规划。比如现有的日志有三组,每组一个成员,并且每个成员大小为50M,那么对于生产
有时随着业务的发展需要对redo log日志进行重新规划。比如现有的日志有三组,每组一个成员,并且每个成员大小为50M,那么对于生产库显然不合理。我们则需要根据业务数据进行相应的调整。一般情况下我们建议每组有两个成员就够了,一个文件大小不超过2G,操作步骤如下:
1、建立日志组:
alter database add logfile group 1
('/opt/Oracle/redo01a.log',
'/opt/oracle/redo01b.log')
size 2G;
2、创建几组日志组后,我们需要将之前不用的日志组给切换成INACTIVE状态,,语法:
alter system switch logfile;
如果想删除的日志组状态一直是active状态,可以用
alter system checkpoint;
这样active就会变成inactive了
3、删除日志组
alter database drop logfile group n;
4、这个只是逻辑删除,还需要去磁盘中把没用的物理文件给删除了
本文永久更新链接地址:

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