5、安裝MySql

• 配置安裝YUM源

# 在http://dev.mysql.com/downloads/repo/yum/找到對應(yīng)的版本并下載
# 如：https://repo.mysql.com//mysql57-community-release-el7-10.noarch.rpm

# 安裝源
yum localinstall mysql57-community-release-el7-8.noarch.rpm

• 安裝

yum install mysql-community-server

• 啟動

systemctl start mysqld

• 設(shè)置開機啟動

systemctl enable mysqld
systemctl daemon-reload

• 查看root用戶原始密碼

grep 'temporary password' /var/log/mysqld.log

• 登錄MySql，并修改root用戶密碼

mysql -uroot -p

# 在MySql命令行下
mysql> set password for 'root'@'localhost'=password('NewPass1!'); 

• 退出MySql命令行

mysql> exit

• 重啟MySql

systemctl restart mysqld

• 附：修改默認(rèn)編碼為utf-8

# 在MySql命令行下
# 查看編碼
mysql> show variables like '%character%';
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8                       |
| character_set_connection | utf8                       |
| character_set_database   | latin1                     |
| character_set_filesystem | binary                     |
| character_set_results    | utf8                       |
| character_set_server     | latin1                     |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+

# 修改/etc/my.cnf配置文件，在[mysqld]下添加編碼配置，如下所示：
[mysqld]
character_set_server=utf8
init_connect='SET NAMES utf8'

# 重啟MySql，再次查看編碼
mysql> show variables like '%character%';
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8                       |
| character_set_connection | utf8                       |
| character_set_database   | utf8                       |
| character_set_filesystem | binary                     |
| character_set_results    | utf8                       |
| character_set_server     | utf8                       |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+

• 附：修改密碼策略，使之可以使用簡易密碼

# 在MySql命令行下
mysql> SHOW VARIABLES LIKE 'validate_password%';
+--------------------------------------+--------+
| 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      |
+--------------------------------------+--------+

mysql> SET GLOBAL validate_password_length = 3;
mysql> SET GLOBAL validate_password_number_count = 0;
mysql> SET GLOBAL validate_password_mixed_case_count = 0;
mysql> SET GLOBAL validate_password_special_char_count = 0;

# 然后就可以修改簡易密碼了
mysql> set password for 'root'@'localhost'=password('root'); 

• 附：開啟root用戶遠(yuǎn)程登陸

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

update user set host='%' where user ='root';
flush privileges;