在前一篇博客中我们提到了如何启动或关闭Oracle的归档(ARCHIVELOG)模式(http://www.linuxidc.com/Linux/2014-10/108120.htm),
v$recovery_file_dest; v$flash_recovery_area_usage; v$flash_recovery_area_usage; v$version;
归档日志文件目录、最大值(已经设定为20G)、当前使用值
可以看到ARCHIVED LOG的使用率是3.84%,这是因为我已经删除掉归档日志文件了。在没有删除归档日志之前是99.46这样打的数字,表明我们的归档日志已经使用了大部分的空间。
所以进入rman程序删除归档日志
rman target sys/pass@prjdb crosscheck archivelog all; ; expired archivelog all;--删除过期日志
深层分析
后来我想这样手动删除也不是个办法总得让系统自动删除。后来就做了数据库备份脚本。执行的备份策略如下:
因为我没有设定归档日志的有效期,所以一档完成增量备份,那么之前的所有归档日志都会被删除,相当于只保留一天的归档日志。在执行这个备份策略以后,发现还是会出现ORA-00257这样的错误。这个时候已经不是简单删除归档日志的问题了,因为当前的归档日志目录连一天的归档日志都发布下。所以考虑扩大归档日志目录,参考:
SQL;---设置使用空间大小(),20GB System altered SQL> show parameter db_recovery_file_dest;---查看归档日志路径限额
此时归档日志目录最大值就变成了20G。按照这样的设定再次重启oralce。
实例最近在进行历史数据导入的工作。要往我的数据库当中导入2G的历史记录,插入记录有几百万条。此时数据库处于归档模式,对于每一个插入操作都会记录到归档日志当中去。在执行这个历史导入操作后3个小时,归档日志就写满了。此时我的问题就来了,如果归档日志写满的,我们的历史导入操作还能正常进行吗?是否还能往数据库当中insert数据。在跟公司DBA请教一番以后得到答复,如果处于归档模式,,并且归档日志写满,那么我的历史数据导入操作会block中,直到我清空归档日志以后导入工作才能再进行。
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本文永久更新链接地址:

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