11 mysql物理结构-日志文件-错误日志

介绍mysql物理结构

包含四种主要的数据文件
    1. 日志文件  包括错误日志、
    2. 数据文件 
    3. 复制相关文件
    4. 其他小文件






下面的操作先介绍 错误日志 的使用

1. 首先 我们没有指定 --log-error 文件，那么会默认生成一个 hostname.err
的日志文件

ywx@ywx:/opt/mysql5151$ ./bin/mysqld_safe --defaults-file=./my.cnf --user=ywx &
[1] 10331
ywx@ywx:/opt/mysql5151$ 110804 12:15:15 mysqld_safe Logging to

'/opt/mysql5151/data/ywx.err'.  生成的路径
110804 12:15:15 mysqld_safe Starting mysqld daemon with databases from /opt/mysql5151/data

ywx@ywx:/opt/mysql5151$ ./bin/mysql --defaults-file=./my.cnf
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.1.51bbk Source distribution

Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL v2 license

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

指定了默认的 错误日志文件
mysql> show variables like '%error%'; 参看日志文件路径
+--------------------+-----------------------------+
| Variable_name      | Value                       |
+--------------------+-----------------------------+
| error_count        | 0                           |
| log_error          | /opt/mysql5151/data/ywx.err |
| max_connect_errors | 10                          |
| max_error_count    | 64                          |
| slave_skip_errors  | OFF                         |
+--------------------+-----------------------------+
5 rows in set (0.00 sec)
mysql> system hostname
ywx

2. 如果我们指定了 --log-error

ywx@ywx:/opt/mysql5151$ ./bin/mysqld_safe --defaults-file=./my.cnf --user=ywx --log-error=/tmp/mysql3306.err &


将日志文件定位到了 /tmp/mysql3306.err 文件

ywx@ywx:/opt/mysql5151$ ps -ef | grep mysql
ywx      10502  8299  0 12:20 pts/0    00:00:00 /bin/sh ./bin/mysqld_safe --defaults-

file=./my.cnf --user=ywx --log-error=/tmp/mysql3306.err

错误日志文件 记录了启动记录

110804 12:20:49 mysqld_safe Starting mysqld daemon with databases from /opt/mysql5151/data
110804 12:20:49 [Warning] '--skip-locking' is deprecated and will be removed in a future

release. Please use '--skip-external-locking' instead.
110804 12:20:49  InnoDB: Started; log sequence number 0 44233
110804 12:20:49 [Note] Event Scheduler: Loaded 0 events
110804 12:20:49 [Note] /opt/mysql5151/libexec/mysqld: ready for connections.
Version: '5.1.51bbk'  socket: '/tmp/mysql.sock'  port: 3306  Source distribution