SESSION_VARIABLES

SESSION_VARIABLES 表提供了关于 session 变量的信息。表中的数据跟 SHOW SESSION VARIABLES 语句执行结果类似。

1. USE information_schema;
2. DESC session_variables;

1. +----------------+---------------+------+------+---------+-------+
2. | Field          | Type          | Null | Key  | Default | Extra |
3. +----------------+---------------+------+------+---------+-------+
4. | VARIABLE_NAME  | varchar(64)   | YES  |      | NULL    |       |
5. | VARIABLE_VALUE | varchar(1024) | YES  |      | NULL    |       |
6. +----------------+---------------+------+------+---------+-------+
7. 2 rows in set (0.00 sec)

1. SELECT * FROM session_variables ORDER BY variable_name LIMIT 10;

1. +-----------------------------------+------------------+
2. | VARIABLE_NAME                     | VARIABLE_VALUE   |
3. +-----------------------------------+------------------+
4. | allow_auto_random_explicit_insert | off              |
5. | auto_increment_increment          | 1                |
6. | auto_increment_offset             | 1                |
7. | autocommit                        | 1                |
8. | automatic_sp_privileges           | 1                |
9. | avoid_temporal_upgrade            | 0                |
10. | back_log                          | 80               |
11. | basedir                           | /usr/local/mysql |
12. | big_tables                        | 0                |
13. | bind_address                      | *                |
14. +-----------------------------------+------------------+
15. 10 rows in set (0.00 sec)

SESSION_VARIABLES 表各列字段含义如下：

• VARIABLE_NAME：数据库中 session 级变量的名称。
• VARIABLE_VALUE：数据库中对应该 session 变量名的具体值。