查看系统环境：

cat /etc/redhat-release

uname -r    uname -m 

注意：不要使用yum的删除功能删除软件，会删除相关依赖，导致意外问题。

 yum install gcc gcc-c++ -y

安装mysql 5.5

tar xf cmake-2.8.8.tar.gz

./configure

gmake  

gmake install

yum install ncurses-devel -y

tar xf mysql-5.5.32.tar.gz

cmake -DCMAKE_INSTALL_PREFIX=/application/mysql-5.5.32 \

-DMYSQL_DATADIR=/application/mysql-5.5.32/data \

-DMYSQL_UNIX_ADDR=/application/mysql-5.5.32/tmp/mysql.sock \

-DDEFAULT_CHARSET=utf8 \

-DDEFAULT_COLLATION=utf8_general_ci \

-DEXTRA_CHARSETS=gbk.gb2312.utf8.ascii \

-DENABLED_LOCAL_INFILE=ON \

-DWITH_INNOBASE_STORAGE_ENGINE=1 \

-DWITH_FEDERATED_STORAGE_ENGINE=1 \

-DWITH_BLACKHOLE_STORAGE_ENGINE=1 \

-DWITHOUT_EXAMPLE_STORAGE_ENGINE=1 \

-DWITHOUT_PARTITION_STORAGE_ENGINE=1 \

-DWITH_FAST_MUTEXES=1 \

-DWITH_ZLIB=bundled \

-DENABLED_LOCAL_INFILE=1 \

-DWITH_READLINE=1 \

-DWITH_EMBEDDED_SERVER=1 \

-DWITH_DEBUG=0\

make&make install

ln -s /application/mysql-5.5.32/  /application/mysql

#useradd mysql -s /sbin/nologin -M -g mysql

2、配置文件

/bin/cp mysql-5.5.32/support-files/my-smail.cnf /etc/my.cnf

3、配置环境变量

export PATH=/application/mysql/bin:$PATH >>/etc/profile

tail -l /etc/profile

source /etc/profile

echo $PATH

环境变量出错解决：http://oldboy.blog.51cto.com/2561410/1122867  

ls错误：PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

4、初始化数据文件（容易出错的步骤）

建立mysql数据文件目录

chown -R mysql.mysql /application/mysql

授权mysql用户访问mysql的安装目录

chmod -R 1777 /tmp

初始化数据库

cd /application/mysql/scripts/

chmod +x mysql_install_db

./mysql_install_db --basedir=/application/mysql/ --datadir=/application/mysql/data/ --user=mysql

grep 'mysql.server' -r /etc/

/bin/cp support-files/mysql.server /etc/init.d/mysqld

chmod +x /etc/init.d/mysqld

/etc/init.d/mysqld start

出现Access 错误

pkill mysqld

lsof -i :3306

rm -fr /application/mysql/data/*

./mysql_install_db --basedir=/application/mysql/ --datadir=/application/mysql/data/ --user=mysql

简单优化(安全木桶原则，最低点做起)：

select user,host,password from mysql.user;

delete from mysql.user where user='';

select user,host,password from mysql.user;

delete from mysql.user where host='www';

delete from mysql.user where host=';;1';

drop databases test;

delete from mysql.user where host!='localhost' or host!='127.0.0.1';

或者干脆全部删除，添加额外管理员

delete from mysql.user;

grant all privileges on *.* to system@'localhost' identified by 'wyy' with grant option; 

with grant option 可以授权用户

flush privileges;

增加密码

/application/mysql//bin/mysqladmin -u root password 'wyy123'

字符集

/etc/sysconfig/il8n

#LANG="zh_CN.GBI8030"

LANG="zh_CN.UTF-8"