MySQL 权限问题：尽管授予角色权限，但用户看不到数据库

Question

在数据库上以root 用户身份运行：

MariaDB [(none)]> SHOW GRANTS FOR jake@localhost;
+-------------------------------------------------------------------------------------------------------------+
| Grants for jake@localhost                                                                                   |
+-------------------------------------------------------------------------------------------------------------+
| GRANT developer TO 'jake'@'localhost'                                                                       |
| GRANT USAGE ON *.* TO 'jake'@'localhost' IDENTIFIED BY PASSWORD '*intentionallyomitted' |
+-------------------------------------------------------------------------------------------------------------+
2 rows in set (0.000 sec)

MariaDB [(none)]> SHOW GRANTS FOR developer;
+-------------------------------------------------+
| Grants for developer                            |
+-------------------------------------------------+
| GRANT USAGE ON *.* TO 'developer'               |
| GRANT ALL PRIVILEGES ON `test`.* TO 'developer' |
+-------------------------------------------------+
2 rows in set (0.000 sec)

MariaDB [(none)]> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.002 sec)

MariaDB [(none)]> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
4 rows in set (0.001 sec)

MariaDB [(none)]> 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
MariaDB [mysql]> SELECT Host, User, is_role, default_role FROM user WHERE User = 'jake' OR User = 'developer';
+-----------+-----------+---------+--------------+
| Host      | User      | is_role | default_role |
+-----------+-----------+---------+--------------+
|           | developer | Y       |              |
| localhost | jake      | N       |              |
+-----------+-----------+---------+--------------+
2 rows in set (0.001 sec)

MariaDB [mysql]> SELECT * FROM roles_mapping WHERE User = 'jake';
+-----------+------+-----------+--------------+
| Host      | User | Role      | Admin_option |
+-----------+------+-----------+--------------+
| localhost | jake | developer | N            |
+-----------+------+-----------+--------------+
1 rows in set (0.001 sec)

然后，在运行sudo systemctl restart mysql之后：

$ mysql -u jake -p
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 11
Server version: 10.3.13-MariaDB-1:10.3.13+maria~bionic mariadb.org binary distribution

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

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

MariaDB [(none)]> SELECT CURRENT_USER;
+----------------+
| CURRENT_USER   |
+----------------+
| jake@localhost |
+----------------+
1 row in set (0.000 sec)

MariaDB [(none)]> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema |
+--------------------+
1 row in set (0.001 sec)

似乎我通过授予developer 角色权限，然后将用户添加到该角色，显然将jake@localhost 用户权限授予了测试数据库。但是，用户看不到数据库（或其中的表）。

这只是我代码中某个地方的愚蠢错字吗？什么可能导致这样的问题？我的一个想法是，这是与IDENTIFED BY PASSWORD 子句有关的问题，因为它只出现在GRANT USAGE 上而没有其他地方出现，但我很难想象这会导致这样的错误。有a related thread，但由于用户到处都是jake@localhost（始终如一），因此该线程中的解决方案似乎都不是问题。那么是什么给出的呢？

版本：

$ mysql --version
mysql  Ver 15.1 Distrib 10.3.13-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2

Answer 1

经过一些额外的烦躁之后，我意识到我没有将角色设为默认值，也没有在我正在使用的会话中设置它。运行 SET ROLE developer; 解决了这个问题。