针对Linux系统自带数据库不能使用的情况，可能是在安装过程有没有安装mysql server，安装时即使选了安装MYSQL(图形界面安装)，只有打开旁边“细节”，从里面勾选选上server才可以。

安装完成后在/usr/bin目录下会生成许多MySQL的相关文件，其中有一个名为mysqld_safe启动服务的脚本文件，执行这个脚本文件后，发现错误'/var/lib/mysql/mysql.sock'，查看mysql服务才发现，没有起来，于是执行/etc/init.d/mysqld start，启动服务后，在/usr/bin执行mysql成功进入数据库！

[pan@localhost ~]$ su – root

Password:

[root@localhost ~]# cd /usr/bin

[root@localhost bin]#./mysqld_safe --user=root &

[1] 12969

[root@localhost bin]# Starting mysqld daemon with databases from /var/lib/mysql

STOPPING server from pid file /var/run/mysqld/mysqld.pid

090606 15:20:04mysqld ended

mysql

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

[1]+Done./mysqld_safe --user=root

[root@localhost bin]# mysql

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

[root@localhost bin]#/etc/rc.d/init.d/mysqld status

mysqld is stopped

[root@localhost bin]# /etc/init.d/mysqld start(或者service mysqld restart，而service mysqld stop停止mysql的服务)

Initializing MySQL database:[OK]

Starting MySQL:[OK]

[root@localhost bin]# mysql

Welcome to the MySQL monitor.Commands end with ; or \g.

Your MySQL connection id is 2 to server version: 4.1.22

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql>

现在进行环境变量的配置，可以针对用户配置用户的环境变量，以root用户例，

[root@localhost bin]# cd

[root@localhost ~]# ls –a(.bash_profile是个隐藏文件，所以要-a)

. Desktop.gstreamer-0.8.mozilla

...dmrc.gtkrc.mysql_history

anaconda-ks.cfg.eggcups.gtkrc-1.2-gnome2.nautilus

.bash_history.fullcircle.ICEauthority.recently-used

.bash_logout.gconf.icons.rhn-applet.conf

.bash_profile.gconfdinstall.log.tcshrc

.bashrc.gnomeinstall.log.syslog.viminfo

.config.gnome2.kde.xauthC1s54N

.cshrc.gnome2_private.metacity.xautheKBniS

[root@localhost ~]# vi .bash_profile(进行修改)

# .bash_profile

# Get the aliases and functions

if [ -f ~/.bashrc ]; then

. ~/.bashrc

fi

# User specific environment and startup programs

PATH=$PATH:$HOME/bin:/usr/bin(此处添加注意冒号)

export PATH

unset USERNAME

[root@localhost ~]# source .bash_profile(更新一下配置文件)

也可以针对系统环境配置，如下：

[root@localhost ~]# vi /etc/profile

# /etc/profile

# System wide environment and startup programs, for login setup

# Functions and aliases go in /etc/bashrc

pathmunge () {

if ! echo $PATH | /bin/egrep -q "(^|:)$1($|:)" ; then

if [ "$2" = "after" ] ; then

PATH=$PATH:$1

else

PATH=$1:$PATH

fi

fi

}

# Path manipulation

if [ `id -u` = 0 ]; then

pathmunge /sbin

pathmunge /usr/sbin

pathmunge /usr/local/sbin

pathmunge /usr/bin

fi