【linux】【mysql】mysql8.0开启远程访问及常见问题

1.连接数据库

 [root@localhost ~]# mysql -uroot -p
 Enter password:
 Welcome to the MySQL monitor.  Commands end with ; or \g.
 Your MySQL connection id is 17
 Server version: 8.0.17 MySQL Community Server - GPL

 Copyright (c) 2000, 2019, 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> 

2.在mysql8版本中更改用户密码需要加入with mysql_native_password

 mysql>  alter user 'root'@'localhost' identified with mysql_native_password by '***
';
 Query OK, 0 rows affected (0.04 sec)

3.修改root用户的host为‘%’

 mysql> show databases;
 +--------------------+
 | Database           |
 +--------------------+
 | information_schema |
 | mysql              |
 | performance_schema |
 | sys                |
 +--------------------+
 4 rows in set (0.01 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> select user,host from user;
 +------------------+-----------+
 | user             | host      |
 +------------------+-----------+
 | mysql.infoschema | localhost |
 | mysql.session    | localhost |
 | mysql.sys        | localhost |
 | root             | localhost |
 +------------------+-----------+
 4 rows in set (0.00 sec)

 mysql> update user set host = '%' where user = 'root';
 Query OK, 1 row affected (0.00 sec)
 Rows matched: 1  Changed: 1  Warnings: 0

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

再查看root用户的host

 mysql> select user,host from user;
 +------------------+-----------+
 | user             | host      |
 +------------------+-----------+
 | root             | %         |
 | mysql.infoschema | localhost |
 | mysql.session    | localhost |
 | mysql.sys        | localhost |
 +------------------+-----------+
 4 rows in set (0.01 sec)

至此，root用户的远程访问已开启。

4.测试下navicat连接

连接成功！

常见问题解决

1.解决sql_mode=only_full_group_by问题

[Err] 1055 - Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'mingbyte.u.USER_ID' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

连接数据库，通过  select version(), @@sql_mode; 查看mode

 [root@localhost ~]# mysql -uroot -p
 Enter password:
 Welcome to the MySQL monitor.  Commands end with ; or \g.
 Your MySQL connection id is 89
 Server version: 8.0.17 MySQL Community Server - GPL

 Copyright (c) 2000, 2019, 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> select version(), @@sql_mode;
 +-----------+-----------------------------------------------------------------------------------------------------------------------+
 | version() | @@sql_mode                                                                                                            |
 +-----------+-----------------------------------------------------------------------------------------------------------------------+
 | 8.0.17    | ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION |
 +-----------+-----------------------------------------------------------------------------------------------------------------------+
 1 row in set (0.00 sec)

 mysql> 

发现上文中查看的mode中有ONLY_FULL_GROUP_BY。将其删除

sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION'

修改mysql的配置文件，重启依旧生效

• vi /etc/my.cnf

将上述sql_mode插入[mysqld]下方，保存，重启数据库，问题解决。

或者

 mysql> set global sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION';
 Query OK, 0 rows affected (0.01 sec)

 mysql> set session sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION';
 Query OK, 0 rows affected (0.00 sec)

问题解决。