[转载]mysql的binlog安全删除

[转载]mysql的binlog安全删除
理论上，应该在配置文件/etc/my.cnf中加上binlog过期时间的配置项，expire_logs_days = 10但是如果没有加这一项，随着产生越来越多的binlog，磁盘被吃掉了不少。可以直接删除binlog文件，但是可以通过mysql提供的工具来删除更安全。因为purge会更新mysql-bin.index中的条目，而直接删除的话，mysql-bin.index文件不会更新。mysql-bin.index的作用是加快查找binlog文件的速度。先help一下吧：mysql> help purgeName: 'PURGE MASTER LOGS'Description:Syntax:PURGE {MASTER | BINARY} LOGS TO 'log_name'PURGE {MASTER | BINARY} LOGS BEFORE 'date'Deletes all the binary logs listed in the log index prior to thespecified log or date. The logs also are removed from the list recordedin the log index file, so that the given log becomes the first.This statement has no effect if the --log-bin option has not beenenabled.URL: http://dev.mysql.com/doc/refman/5.0/en/purge-master-logs.htmlExamples:PURGE MASTER LOGS TO 'mysql-bin.010';PURGE MASTER LOGS BEFORE '2003-04-02 22:46:26'; 两种方法都可用。第一个是删除至某一个文件为止，第二个是删除到某个日期为止。比如我们让它保留近3天的log，可以这样PURGE MASTER LOGS BEFORE '2010-10-17 00:00:00'; 看下执行前后的文件数：执行前：part2# ls mysql-bin.*|wc -l 243执行purge：mysql> PURGE MASTER LOGS BEFORE '2010-10-17 00:00:00';Query OK, 0 rows affected (0.02 sec)执行后：part2# ls mysql-bin.* | wc -l 88可见把17号前的binlog全部删除了。 需要注意的是：最好到slave上面去看下当前同步到那个binlog文件了，用show slave status查看。否则，master上删多了的话，就造成slave缺失日志文件而导致数据不一致了。

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