这篇文章主要介绍“如何理解MySQL用户中的百分号%是否包含localhost”，在日常操作中，相信很多人在如何理解MySQL用户中的百分号%是否包含localhost问题上存在疑惑，小编查阅了各式资料，整理出简单好用的操作方法，希望对大家解答”如何理解MySQL用户中的百分号%是否包含localhost”的疑惑有所帮助！接下来，请跟着小编一起来学习吧！
1 前言
操作MySQL的时候发现，有时只建了%的账号，可以通过localhost连接，有时候却不可以，网上搜索也找不到满意的答案，干脆手动测试一波
2 两种连接方法
这里说的两种连接方法指是执行mysql命令时，-h参数填的是localhost还是IP, 两种连接方式的区别如下
-h 参数为 localhost
当-h参数为localhost的时候，实际上是使用socket连接的（默认连接方式）, 实例如下
[mysql@mysql-test-83 ~]$ /usr/local/mysql57/bin/mysql -utest_user -p -hlocalhost
Enter password:
========= 省略 ===========
mysql> status
/usr/local/mysql57/bin/mysql Ver 14.14 Distrib 5.7.21, for linux-glibc2.12 (x86_64) using EditLine wrapper
Connection id: 9
Current database:
Current user: test_user@localhost
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.7.21-log MySQL Community Server (GPL)
Protocol version: 10
Connection: Localhost via UNIX socket从Current user可以看到用户是xx@localhost, 连接方式为Localhost via UNIX socket
-h 参数为 IP
当-h参数为IP的时候，实际上是使用TCP连接的, 实例如下
[mysql@mysql-test-83 ~]$ /usr/local/mysql57/bin/mysql -utest_user -p -h227.0.0.1
Enter password:
========= 省略 ===========
mysql> status
--------------
/usr/local/mysql57/bin/mysql Ver 14.14 Distrib 5.7.21, for linux-glibc2.12 (x86_64) using EditLine wrapper
Connection id: 11
Current database:
Current user: test_user@127.0.0.1
SSL: Cipher in use is DHE-RSA-AES256-SHA
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.7.21-log MySQL Community Server (GPL)
Protocol version: 10
Connection: 127.0.0.1 via TCP/IP
Server characterset: utf8从Current user可以看到用户是xx@127.0.0.1, 连接方式为TCP/IP
3 不同版本的差别
测试方法就是看能不能连接，如果不想看测试过程可以拉到最后看结论
3.1 MySQL 8.0
创建用户
mysql> select version();
+-----------+
| version() |
+-----------+
| 8.0.11 |
+-----------+
1 row in set (0.00 sec)
mysql> create user test_user@'%' identified by 'test_user';
Query OK, 0 rows affected (0.07 sec)使用 localhost 登录
[root@mysql-test-72 ~]# /usr/local/mysql80/bin/mysql -utest_user -p -hlocalhost
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 9
Server version: 8.0.11 MySQL Community Server - GPL
========= 省略 ===========
mysql> status
--------------
/usr/local/mysql80/bin/mysql Ver 8.0.11 for linux-glibc2.12 on x86_64 (MySQL Community Server - GPL)
Connection id: 9
Current database:
Current user: test_user@localhost
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 8.0.11 MySQL Community Server - GPL
Protocol version: 10
Connection: Localhost via UNIX socket
...使用 IP 登录
[root@mysql-test-72 ~]# /usr/local/mysql80/bin/mysql -utest_user -p -h227.0.0.1
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.11 MySQL Community Server - GPL
========= 省略 ===========
mysql> status
--------------
/usr/local/mysql80/bin/mysql Ver 8.0.11 for linux-glibc2.12 on x86_64 (MySQL Community Server - GPL)
Connection id: 8
Current database:
Current user: test_user@127.0.0.1
SSL: Cipher in use is DHE-RSA-AES128-GCM-SHA256
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 8.0.11 MySQL Community Server - GPL
Protocol version: 10
Connection: 127.0.0.1 via TCP/IP结果显示8.0版本的MySQL, % 包括localhost
3.2 MySQL 5.7
创建 % 用户
db83-3306>>create user test_user@'%' identified by 'test_user';
Query OK, 0 rows affected (0.00 sec)使用 localhost 登录
[mysql@mysql-test-83 ~]$ /usr/local/mysql57/bin/mysql -utest_user -p -hlocalhost
========= 省略 ===========
mysql> status
/usr/local/mysql57/bin/mysql Ver 14.14 Distrib 5.7.21, for linux-glibc2.12 (x86_64) using EditLine wrapper
Connection id: 9
Current database:
Current user: test_user@localhost
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.7.21-log MySQL Community Server (GPL)
Protocol version: 10
Connection: Localhost via UNIX socket
....使用 IP 登录
[mysql@mysql-test-83 ~]$ /usr/local/mysql57/bin/mysql -utest_user -p -h227.0.0.1
Enter password:
========= 省略 ===========
mysql> status
--------------
/usr/local/mysql57/bin/mysql Ver 14.14 Distrib 5.7.21, for linux-glibc2.12 (x86_64) using EditLine wrapper
Connection id: 11
Current database:
Current user: test_user@127.0.0.1
SSL: Cipher in use is DHE-RSA-AES256-SHA
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.7.21-log MySQL Community Server (GPL)
Protocol version: 10
Connection: 127.0.0.1 via TCP/IP
Server characterset: utf8
...结果显示5.7版本的MySQL, % 包括localhost
3.3 MySQL 5.6
创建用户
db83-3306>>select version();
+------------+
| version() |
+------------+
| 5.6.10-log |
+------------+
1 row in set (0.00 sec)
db83-3306>>create user test_user@'%' identified by 'test_user';
Query OK, 0 rows affected (0.00 sec)使用 localhost 登录
[mysql@mysql-test-83 ~]$ /usr/local/mysql57/bin/mysql -utest_user -p -hlocalhost
Enter password:
ERROR 1045 (28000): Access denied for user 'test_user'@'localhost' (using password: YES)使用 IP 登录
[mysql@mysql-test-83 ~]$ /usr/local/mysql57/bin/mysql -utest_user -p -h227.0.0.1
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.6.10-log MySQL Community Server (GPL)
========= 省略 ===========
mysql> status
--------------
/usr/local/mysql57/bin/mysql Ver 14.14 Distrib 5.7.21, for linux-glibc2.12 (x86_64) using EditLine wrapper
Connection id: 3
Current database:
Current user: test_user@127.0.0.1
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.6.10-log MySQL Community Server (GPL)
Protocol version: 10
Connection: 127.0.0.1 via TCP/IP
......
--------------结果显示MySQL 5.6的%不包括localhost
3.4 MySQL 5.1
创建用户
mysql> select version();
+-----------+
| version() |
+-----------+
| 5.1.73 |
+-----------+
1 row in set (0.00 sec)
mysql> create user test_user@'%' identified by 'test_user';
Query OK, 0 rows affected (0.00 sec)使用 localhost 登录
[root@chengqm ~]# mysql -utest_user -p
Enter password:
ERROR 1045 (28000): Access denied for user 'test_user'@'localhost' (using password: YES)使用 IP 登录
[root@chengqm ~]# mysql -utest_user -p -h227.0.0.1
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 4901339
Server version: 5.1.73 Source distribution
========= 省略 ===========
mysql> status
--------------
mysql Ver 14.14 Distrib 5.1.73, for redhat-linux-gnu (x86_64) using readline 5.1
Connection id: 4901339
Current database:
Current user: test_user@127.0.0.1
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.1.73 Source distribution
Protocol version: 10
Connection: 127.0.0.1 via TCP/IP结果显示 5.1 版本的%不包括localhost
3.5 MariaDB 10.3
创建用户
db83-3306>>select version();
+---------------------+
| version() |
+---------------------+
| 10.3.11-MariaDB-log |
+---------------------+
1 row in set (0.000 sec)
db83-3306>>create user test_user@'%' identified by 'test_user';
Query OK, 0 rows affected (0.001 sec)使用 localhost 登录
[mysql@mysql-test-83 ~]$ /usr/local/mariadb/bin/mysql -utest_user -p -hlocalhost
Enter password:
ERROR 1045 (28000): Access denied for user 'test_user'@'localhost' (using password: YES)使用 IP 登录
[mysql@mysql-test-83 ~]$ /usr/local/mariadb/bin/mysql -utest_user -p -h227.0.0.1
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 12
Server version: 10.3.11-MariaDB-log MariaDB Server
========= 省略 ===========
MariaDB [(none)]> status
--------------
/usr/local/mariadb/bin/mysql Ver 15.1 Distrib 10.3.11-MariaDB, for Linux (x86_64) using readline 5.1
Connection id: 12
Current database:
Current user: test_user@127.0.0.1
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server: MariaDB
Server version: 10.3.11-MariaDB-log MariaDB Server
Protocol version: 10
Connection: 127.0.0.1 via TCP/IP结果显示MariaDB 10.3的%不包括localhost
4 结论
| 版本 | 用户中的%是否包括localhost |
|---|---|
| MySQL8.0 | 包括 |
| MySQL5.7 | 包括 |
| MySQL5.6 | 不包括 |
| MySQL5.1 | 不包括 |
| MariaDB 10.3 | 不包括 |
到此，关于“如何理解MySQL用户中的百分号%是否包含localhost”的学习就结束了，希望能够解决大家的疑惑。理论与实践的搭配能更好的帮助大家学习，快去试试吧！若想继续学习更多相关知识，请继续关注亿速云网站，小编会继续努力为大家带来更多实用的文章！
