我下载的是目前最新的版本mysql-5.0.45-linux-i686.tar.gz
安装过程：
su 到root 权限。
#tar -zvxf mysql-5.0.45-linux-i686.tar.gz
#mv mysql-5.0.45/ /usr/local/mysql
#cd /usr/local/mysql
#groupadd mysql
#useradd -g mysql mysql
#chown -R mysql .
#chgrp -R mysql .
#scripts/mysql_install_db --user=mysql
#chown -R root .
#chown -R mysql data
#bin/mysqld_safe --user=mysql &
按照官方文档说这就应该能启动了，可是报错如下：
nohup: ignoring input and redirecting stderr to stdout
Starting mysqld daemon with databases from /var/lib/mysql
STOPPING server from pid file /var/run/mysqld/mysqld.pid
071112 00:22:06 mysqld ended
查看日志：
＃less /var/log/mysqld.log
其中有一段如下：
071112 0:22:06 [ERROR] /usr/local/mysql/bin/mysqld: Can’t create/write to file ’/var/run/mysqld/mysqld.pid’ (Errcode: 2)
071112 0:22:06 [ERROR] Can’t start server: can’t create PID file: No such file or directory
071112 00:22:06 mysqld ended
#cd /var/run/
#ls
mysqld目录不存在
#mkdir /var/run/mysqld
#cd /var/run/mysqld
创建文件mysqld.pid
#touch mysqld.pid
#cd..
#chown -R mysql mysqld .
#cd /usr/local/mysql/
#bin/mysqld_safe --user=mysql &
nohup: ignoring input and redirecting stderr to stdout
Starting mysqld daemon with databases from /var/lib/mysql