centos 安装mysql

卸载mysql

rpm -qa|grep -i mysql
# 卸载命令
yum -y remove + list_name

yum安装

cd /usr/local/src/

wget http://repo.mysql.com/mysql57-community-release-el7-8.noarch.rpm

rpm -ivh mysql57-community-release-el7-8.noarch.rpm

yum -y install mysql-server

指定安装目录
yum --installroot=/usr/local/mysql --releasever=/ -y install mysql-server ）我没试，这样装环境变量配置都不用你管，装上直接启动就行。安装路径是默认的。

默认配置文件路径
/etc/my.conf

启动mysql服务

service mysqld restart

查看初始密码

grep "password" /var/log/mysqld.log

报错 You must reset your password using ALTER USER statement before executing this statement.

SET PASSWORD = PASSWORD('Root!!2020');

ALTER USER 'root'@'localhost' PASSWORD EXPIRE NEVER;

flush privileges;

---

重置mysql 密码

alter user 'root'@'localhost' identified by 'Root!!2020';

flush privileges;

添加新用户

create user 'root'@'%' identified by 'Root!!2020';

grant all on . to 'root'@'%' identified by 'Root!!2020' with grant option;
增加root用户指定可以任意IP登录，如果想限制只能让指定IP登录请把%替换成IP地址

改简单密码

SHOW VARIABLES LIKE 'vali%';
mysql> SHOW VARIABLES LIKE 'vali%';
+--------------------------------------+--------+
| Variable_name | Value |
+--------------------------------------+--------+
| validate_password_check_user_name | OFF |
| validate_password_dictionary_file | |
| validate_password_length | 8 |
| validate_password_mixed_case_count | 1 |
| validate_password_number_count | 1 |
| validate_password_policy | MEDIUM |
| validate_password_special_char_count | 1 |
+--------------------------------------+--------+

密码最小长度

validate_password_length

至少包含小写或大写字母的个数

validate_password_mixed_case_count

至少包含数字的个数

validate_password_number_count

强度等级

validate_password_policy
【0/LOW】：只检查长度。
【1/MEDIUM】：在0等级的基础上多检查数字、大小写、特殊字符。
2/STRONG】：在1等级的基础上多检查特殊字符字典文件，此处为1。

至少要包含的个数字符的个数，此处为1

validate_password_special_char_count

关闭密码强度配置

validate_password =off

更改密码 （字段：authentication_string

update mysql.user set authentication_string=password('root') where user='root' ;

设置密码过期时间

修改配置文件

default_password_lifetime=0
#命令行
ALTER USER 'script'@'localhost' PASSWORD EXPIRE NEVER

忘记密码

修改配置文件

skip-grant-tables
#执行命令
update mysql.user set authentication_string=password('root') where user='root' ;
flush privileges;

windows 删除mysql 服务

使用管理员打开cmd

sc delete MySQL57

修改mysql默认储存路径

创建文件夹

mkdir /var/lib/data/mysql/
# mv 或cp 原始数据库目录文件
cp -a /var/lib/mysql /var/lib/mysql/data

备份my.conf

修改配置文件
[client]
port= 3308
socket= /var/lib/data/mysql/mysql/mysql.sock -----路径改到新的存储目录下/var/lib/data/mysql/mysql

[mysqld]
socket= /var/lib/data/mysql/mysql/mysql.sock -----路径改到新的存储目录下/var/lib/data/mysql/mysql
datadir= /var/lib/data/mysql/mysql -----路径改到新的存储目录下/var/lib/data/mysql/mysql

[mysqld_safe]
socket=/var/lib/data/mysql/mysql/mysql.sock -----路径改到新的存储目录下/var/lib/data/mysql/mysql

[mysql.server]
socket=/var/lib/data/mysql/mysql/mysql.sock -----路径改到新的存储目录下/var/lib/data/mysql/mysql

重启mysql

service mysqld stop
service mysqld start

查看端口是否打开

lsof -i:3306

查看mysql 状态

service mysqld status

php 连接不上

mysql.default_socket =/var/lib/data/mysql/mysql/mysql.sock

查看端口

show global variables like 'port';

查看mysql 权限

select * from user;
show grants for root@'localhost';

升级

mysql_upgrade -u root -p --force

参考

CentOS 7 下使用yum安装MySQL5.7.20 最简单 图文详解