MySQL初体验安装MySQL

操作系统版本：redhat 6.7 64位

[root@mysql ~]# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 6.7 (Santiago)

数据库版本：MySQL5.7

下载地址：https://downloads.mysql.com/archives/community/

我下载的包为：mysql-5.7.24-linux-glibc2.12-x86_64.tar.gz

（一）安装前的准备

（1）查看服务器上是否已经安装了MySQL。RedHat Linux系统安装时，如果选择了MySQL数据库，那么服务器上会存在MySQL数据库，需要先卸载。

# 查看是否存在mysql安装包
[root@mysql etc]# rpm -qa| grep mysql
mysql-community-common-5.7.21-1.el7.x86_64
# 如果存在，需要先卸载
[root@mysql etc]# rpm -e mysql-community-common-5.7.21-1.el7.x86_64

（2）查看服务器上是否存在mariadb数据库。mariadb是MySQL的一个分支，需要卸载

[root@mysql mysql]# rpm -qa |grep mariadb

(3) 删除/etc/my.cnf文件。该文件类似Oracle的参数文件

[root@mysql mysql]# rm /etc/my.cnf
rm: cannot remove `/etc/my.cnf': No such file or directory

（4）创建mysql用户来管理数据库

[root@mysql mysql]# cat /etc/passwd|grep mysql
mysql:x:27:27:MySQL Server:/var/lib/mysql:/bin/bash
[root@mysql mysql]# cat /etc/group |grep mysql
mysql:x:27:如果没有，则创建用户组和用户

[root@mysql mysql]# groupadd mysql
[root@mysql mysql]# useradd -g mysql mysql

修改mysql用户密码：

[root@mysql mysql]# passwd mysql
Changing password for user mysql.
New password:
BAD PASSWORD: it is too short
BAD PASSWORD: is too simple
Retype new password:
passwd: all authentication tokens updated successfully.

（二）安装MySQL数据库

mysql安装路径：/usr/local/mysql/

数据存放位置：：/usr/local/mysql/data

（1）解压MySQL安装包

[root@mysql mysql]# tar -xzvf mysql-5.7.24-linux-glibc2.12-x86_64.tar.gz

（2）将解压后的文件拷贝到安装路径下

[root@mysql mysql]# mv mysql-5.7.24-linux-glibc2.12-x86_64 /usr/local/mysql/

（3）修改文件的权限

[root@mysql mysql]# cd /usr/local/
[root@mysql local]# ls
bin etc games include lib lib64 libexec mysql sbin share src
[root@mysql local]# chown -R mysql mysql/
[root@mysql local]# chgrp -R mysql mysql/

（4）创建存放data的文件夹

[root@mysql mysql]# mkdir data
[root@mysql mysql]# chown -R mysql:mysql data

（5）在/etc下创建mysql的参数文件my.cnf

[root@mysql etc]# vim my.cnf

[mysql]
# 设置mysql客户端默认字符集
default-character-set=utf8
[mysqld]
skip-name-resolve
# 设置3306端口
port = 3306
# 设置mysql的安装目录
basedir=/usr/local/mysql
# 设置mysql数据库的数据的存放目录
datadir=/usr/local/mysql/data
# 允许最大连接数
max_cOnnections=200
# 服务端使用的字符集默认为8比特编码的latin1字符集
character-set-server=utf8
# 创建新表时将使用的默认存储引擎
default-storage-engine=INNODB
lower_case_table_names=1
max_allowed_packet=16M

（6）安装数据库

[root@mysql bin]# pwd
/usr/local/mysql/bin
[root@mysql bin]# ./mysql_install_db --user=mysql --basedir=/usr/local/mysql/ --datadir=/usr/local/mysql/data
2019-04-20 22:17:08 [WARNING] mysql_install_db is deprecated. Please consider switching to mysqld --initialize
2019-04-20 22:17:14 [WARNING] The bootstrap log isn't empty:
2019-04-20 22:17:14 [WARNING] 2019-04-20T14:17:08.662276Z 0 [Warning] --bootstrap is deprecated. Please consider using
2019-04-20T14:17:08.663008Z 0 [Warning] Changed limits: max_open_files: 1024 (requested 5000)
2019-04-20T14:17:08.663018Z 0 [Warning] Changed limits: table_open_cache: 407 (requested 2000)

（6）设置启动项

[root@mysql mysql]# ls
bin COPYING data docs include lib man README share support-files
[root@mysql mysql]# cd ./support-files/mysql
mysqld_multi.server mysql-log-rotate mysql.server
[root@mysql mysql]# cp ./support-files/mysql.server /etc/init.d/mysqld
[root@mysql mysql]# chown 777 /etc/my.cnf
[root@mysql mysql]# chmod a+x /etc/init.d/mysqld

(7)开启数据库

[root@mysql mysql]# /etc/init.d/mysqld start
Starting MySQL. [ OK ]

查看数据库状态

[root@mysql mysql]# service mysqld status
MySQL running (39674) [ OK ]
# 或者
[root@mysql mysql]# ps -ef|grep mysql
mysql 39674 1 0 22:53 pts/0 00:00:01 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --plugin-dir=/usr/local/mysql/lib/plugin --log-error=mysql.err --pid-file=/usr/local/mysql/data/mysql.pid --port=3306
root 40719 3339 0 23:13 pts/0 00:00:00 grep mysql

（8）修改数据库的初始root密码

（8.1）查看初始密码

[root@mysql mysql]# cat /root/.mysql_secret
# Password set for user 'root@localhost' at 2019-04-20 22:17:08
bkro9k_?=jrM

（8.2）使用初始密码登录数据库，修改初始密码为123456

[root@mysql mysql]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.24
mysql> set password=password('123456');
Query OK, 0 rows affected, 1 warning (0.00 sec)
（9）确认数据库状态，运行正常

mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.00 sec)

安装完成。