【体系结构】MySQL 日志文件--错误日志
㈠ 是什么? 记录MySQL Server 启动和关闭的详细信息、以及运行过程中较为严重的警告和错误信息 mysqlgt; show variables like
㈠ 是什么?
记录MySQL Server 启动和关闭的详细信息、以及运行过程中较为严重的警告和错误信息
mysql> show variables like 'log_error';
+---------------+---------------------------------+
| Variable_name | Value |
+---------------+---------------------------------+
| log_error | /home/mysql/mysql/log/alert.log |
+---------------+---------------------------------+
1 row in set (0.01 sec)
为了维护方便需要、有时候会希望将错误日志中的内容做备份并重新开始记录、那么可以:
shell> mv host_name.err host_name.err-old
shell> mysqladmin flush-logs
shell> mv host_name.err-old backup-directory
㈡ 有什么作用?
MySQL DBA 在遇到问题时应该首先查看该文件
当出现 MySQL Server 不能正常启动时、第一个拷问的重点对象应该就是此人
MySQL中的error log日志文件,其实功能跟Oracle中的alert极为相似
不过由名称也看得出MySQL果然还是嫩了点儿
error logs中即不全是error信息,也并非所有error都被记入log,这名称就有点儿名不副实了
还是Oracle高明--alert,就是提示你要注意,咋理解都没毛病

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