Redhat9.2 安装MySQL5.0
一开始学习数据库就是用的MySQL,之后就是Informix，现在是使用ORACLE,现在由于学习研究开发一个基于负载平衡的网络监控系统需要想使用MySQL，
感觉有点生疏，现就MySQL5.0在linux下安装的经验总结一下：
在http://www.mysql.com/downloads/选择要安装的版本，
1.安装MySQL需要下面两个文件：
　　MySQL-server-4.0.16-0.i386.rpm　　　
　　MySQL-client-4.0.16-0.i386.rpm

[root@MT src]# rpm -ivh MySQL-server-community-5.0.41-0.rhel4.i386.rpm
warning: MySQL-server-community-5.0.41-0.rhel4.i386.rpm: V3 DSA signature: NOKEY, key ID 5072e1f5
Preparing...??????????????? ########################################### [100%]
?? 1:MySQL-server-community ########################################### [100%]
PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:
/usr/bin/mysqladmin -u root password 'new-password'
/usr/bin/mysqladmin -u root -h MT password 'new-password'
See the manual for more instructions.
Please report any problems with the /usr/bin/mysqlbug script!

The latest information about MySQL is available on the web at
http://www.mysql.com
Support MySQL by buying support/licenses at http://shop.mysql.com
Starting MySQL.......... SUCCESS!
如碰到安装失败（如perl(DBI)），只要安装相应的软件即可！
同理，安装 MySQL-client-4.0.16-0.i386.rpm
[root@MT src]# rpm -ivh MySQL-client-4.0.16-0.i386.rpm

2.修改MySQL密码
[root@MT src]# mysqladmin -u root password mysql

3.MySQL数据库管理
(1)关闭与启动
[root@MT src]# mysqladmin -u root -p shutdown
[root@MT src]# /et/init.d/mysql start
(2)更换MySQL目录
[root@MT src]# mysqladmin -u root -p shutdown
[root@MT src]# cp /var/lib/mysql /home/mysql/5.0/
[root@MT src]# cp /usr/share/mysql/my-medium.cnf　/etc/my.cnf
[root@MT src]# cp /usr/share/mysql/my-medium.cnf　/etc/my.cnf
[root@MT src]# vi　/etc/my.cnf
# The following options will be passed to all MySQL clients
[client]
#password?????? = your_password
port??????????? = 3306
##Modified content MartriWang@gmail.com
#socket???????? = /var/lib/mysql/mysql.sock
socket????????? = /home/mysql/5.0/mysql/mysql.sock

# Here follows entries for some specific programs

# The MySQL server
[mysqld]
port??????????? = 3306
#socket???????? = /var/lib/mysql/mysql.sock
##Modified content MartriWang@gmail.com
socket????????? = /home/mysql/5.0/mysql/mysql.sock
skip-locking
key_buffer = 16M
max_allowed_packet = 1M
table_cache = 64
sort_buffer_size = 512K
net_buffer_length = 8K
read_buffer_size = 256K
read_rnd_buffer_size = 512K
myisam_sort_buffer_size = 8M

[root@MT src]# vi　/etc/init.d/mysql
# The following variables are only set for letting mysql.server find things.

# Set some defaults
pid_file=
server_pid_file=
use_mysqld_safe=1
user=mysql
if test -z "$basedir"
then
? basedir=/
? bindir=/usr/bin
? if test -z "$datadir"
? then
##Modified content MartriWang@gmail.com
#??? datadir=/var/lib/mysql
???? datadir=/home/mysql/5.0/mysql

[root@MT src]#/etc/init.d/mysql start

(3)MySQL目录
数据库目录：/var/lib/mysql/（可更改，前面已经介绍）
配置文件：/usr/share/mysql（mysql.server命令及配置文件）
相关命令：/usr/bin(mysqladmin mysqldump等命令)
启动脚本：/etc/rc.d/init.d/（ln -s /etc/init.d/）（启动脚本文件mysql的目录）

(4)备份与恢复
备份:[root@MT src]#mysqldump -u root -p --opt mysql > mysql_back
恢复:[root@MT src]#mysql -u root -p mysql < mysql_back