MySQL5.6安装

一、下载MySQL安装包

下载链接：https://dev.mysql.com/downloads/mysql/
文中使用MySQL 5.6.50版本。

二、安装

[[email protected] ~]# cd /usr/local/src/
[[email protected]localhost src]# wget https://cdn.mysql.com//Downloads/MySQL-5.6/mysql-5.6.50-linux-glibc2.12-x86_64.tar.gz
[[email protected] src]# tar -zxf mysql-5.6.50-linux-glibc2.12-x86_64.tar.gz
[[email protected] src]# ln -s /usr/local/src/mysql-5.6.50-linux-glibc2.12-x86_64 /usr/local/mysql

创建软连接主要是方便以后的版本升级等。

三、配置文件

在配置文件中定义MySQL相关路径：

[[email protected] ~]# cat /usr/local/mysql/my.cnf 
[mysqld]
port=3306
bind-address=0.0.0.0
user=mysql
basedir=/usr/local/mysql
datadir=/usr/local/mysql/data
socket=/usr/local/mysql/mysql.sock

四、初始化

创建mysql用户：

[[email protected] ~]# useradd -M -s /sbin/nologin mysql

修改目录的属主和属组为mysql：

[[email protected] ~]# chown -R mysql:mysql /usr/local/mysql/

执行初始化命令：

[[email protected] ~]# /usr/local/mysql/scripts/mysql_install_db --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data/ --defaults-file=/usr/local/mysql/my.cnf 

错误处理：
1）缺少perl模块导致的错误

FATAL ERROR: please install the following Perl modules before executing /usr/local/mysql/scripts/mysql_install_db:
Data::Dumper

安装autoconf解决：

[[email protected] ~]# yum -y install autoconf

2）缺少libaio导致的错误

Installing MySQL system tables.../usr/local/mysql/bin/mysqld: error while loading shared libraries: libaio.so.1: cannot open shared object file: No such file or directory

安装libaio-devel解决：

[[email protected] ~]# yum -y install libaio-devel

五、启动

后台启动：

[[email protected] ~]# /usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/my.cnf &

编写启动脚本：

[[email protected] ~]# cat /usr/local/mysql/start_3306.sh 
#!/bin/bash
ulimit -n 40960
sysctl -w vm.swappiness=0
numactl --interleave=all /usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/my.cnf &

编写停止脚本：

[[email protected] ~]# cat /usr/local/mysql/stop_3306.sh 
#!/bin/bash
/usr/local/mysql/bin/mysqladmin -S /usr/local/mysql/mysql.sock shutdown

脚本添加执行权限：

[[email protected] ~]# chmod 755 /usr/local/mysql/start_3306.sh /usr/local/mysql/stop_3306.sh

六、添加环境变量

MySQL提供了一系列命令，为了方便地执行这些命令，将其添加到环境变量中：

[[email protected] ~]# cat /etc/profile.d/mysql.sh 
export PATH=/usr/local/mysql/bin/:$PATH
[[email protected] ~]# source /etc/profile
[[email protected] ~]# which mysql
/usr/local/mysql/bin/mysql

七、连接MySQL

在本地服务器，通过mysql命令连接数据库：

[[email protected] ~]# which mysql
/usr/local/mysql/bin/mysql
[[email protected] ~]# 
[[email protected] ~]# mysql -h 127.0.0.1

八、使用systemd管理MySQL

在步骤五中，使用shell脚本控制MySQL的启动和停止。这里用CentOS 7系统的systemd管理MySQL：

[[email protected] ~]# cat /usr/lib/systemd/system/mysqld.service
[Unit]
Description=MySQL 5.6.50

[Service]
User=mysql
Group=mysql
LimitNOFILE=40960
Restart=on-failure
ExecStart=/usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/my.cnf

[Install]
WantedBy=multi-user.target
[[email protected] ~]# systemctl daemon-reload
[[email protected] ~]# systemctl enable mysqld       # 将MySQL设置为开机自启动
[[email protected] ~]# systemctl start mysqld        # 启动MySQL
[[email protected] ~]# systemctl status mysqld       # 查看MySQL状态

九、修改root用户密码

9.1、通过mysqladmin命令修改密码

为root用户设置密码：

[[email protected] ~]# mysqladmin -h 127.0.0.1 -u root -p password '123123'

修改root用户密码：

[[email protected] ~]# mysqladmin -h 127.0.0.1 -u root -p'123123' password '123456'

9.2、通过MySQL客户端修改密码

首先执行mysql命令连接到MySQL，再执行设置密码命令：

[[email protected] ~]# mysql -h 127.0.0.1 -u root -p
mysql> set password for [email protected]=password('123123');
Query OK, 0 rows affected (0.00 sec)