mysql5.7.20：安装教程

从mysql官网下载安装包：/mysql-5.7.20-linuxglibc2.12-x86_64.tar.gz

#切换目录
cd /usr/local
#解压下载的安装包
tar -zxvf /software/mysql/mysql-5.7.20-linux-glibc2.12-x86_64.tar.gz
#重命名
mv mysql-5.7.20-linux-glibc2.12-x86_64 mysql
#建立数据存储目录
mkdir data
#建立用户组
groupadd mysql
#建立用户，并禁止用户登录
useradd -r -s /sbin/nologin -g mysql mysql -d /usr/local/mysql
#改变文件归属
chown -R mysql.mysql /usr/local/mysql/
#初始化系统数据库，记住不能用./bin/mysql_install_db，已经过期了
./bin/mysqld --initialize  --user=mysql --basedir=/usr/local/mysql/ --datadir=/usr/local/mysql/data/

初始化后，会打印日志，如下 ,注意看最后输出，红色标记部分，这个就是root的临时密码。

2018-01-12T05:08:12.048923Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see doc umentation for more details).
2018-01-12T05:08:12.228535Z 0 [Warning] InnoDB: New log files created, LSN=45790
2018-01-12T05:08:12.251370Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2018-01-12T05:08:12.305856Z 0 [Warning] No existing UUID has been found, so we a ssume that this is the first time that this server has been started. Generating a new UUID: 968b7130-f756-11e7-8704-000c29009e57.
2018-01-12T05:08:12.306388Z 0 [Warning] Gtid table is not ready to be used. Tabl e 'mysql.gtid_executed' cannot be opened.
2018-01-12T05:08:12.307188Z 1 [Note] A temporary password is generated for root@localhost: LwchxXdoO5*8

配置数据库：

vi /etc/my.cnf

my.cnf内容：

[mysqld]
#目录设置
basedir=/usr/local/mysql
datadir=/usr/local/mysql/data
port=3306

#服务ID
socket=/tmp/mysql.sock

#数据库表名大小写不敏感
lower_case_table_names=1

#设置字符集，防止中文乱码
init_connect='SET collation_connection = utf8_general_ci'
init_connect='SET NAMES utf8'
character-set-server=utf8
collation-server=utf8_general_ci
skip-character-set-client-handshake
[client]
default-character-set=utf8
[mysql]
default-character-set=utf8

安装成服务：

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

启动服务

service mysqld start

登录到mysql

./bin/mysql -u root -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.20

Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> grant all privileges on *.* to root@"%" identified by "2018dlj123!@#0112" with grant option;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.

一开始想做授权，结果发现报错，原因是必须要修改初始密码。

修改初始密码：

mysql> ALTER USER USER() IDENTIFIED BY 'test123456';

Query OK, 0 rows affected (0.00 sec)

mysql> use mysql
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> grant all privileges on *.* to root@"%" identified by "test123456" with grant option;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

至此安装完毕！