同大多数关系型数据库一样，日志文件是MySQL数据库的重要组成部分。MySQL有几种不同的日志文件，通常包括错误日志文件，二进制日志，通用日志，慢查询日志，等等。这些日志可以帮助我们定位mysqld内部发生的事件，数据库性能故障，记录数据的变更历史，用户恢复数据库等等。本文主要描述错误日志文件。
1、MySQL日志文件系统的组成
2、错误日志
3、实战演示
#查看当前的错误日志配置,缺省情况下位于数据目录
#查看当前mysql server错误日志文件
#停止mysql服务器
#使用配置文件来设置log-error参数
#Author : Leshami
#修改my.cnf，删除skip-opt选项
#再次启动mysql服务器
从上面的错误日可以看出，错误日志文件的格式，通常如下
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