注意 从MySQL 5.7.6开始，show_compatibility_56系统变量的值会影响此处描述的表中的可用信息。 有关详细信息，请参见“服务器系统变量”中该变量的说明。
注意 从MySQL 5.7.6开始，此处描述的表中提供的信息也可从Performance Schema获得。 不推荐使用INFORMATION_SCHEMA表,并且将在以后的MySQL版本中删除它们,优先使用Performance Schema表。 有关从INFORMATION_SCHEMA表迁移到性能模式表的建议，请参见“迁移到性能模式系统和状态变量表”。
mysql> select * from GLOBAL_STATUS ; ERROR 3167 (HY000): The 'INFORMATION_SCHEMA.GLOBAL_STATUS' feature is disabled; see the documentation for 'show_compatibility_56' mysql> select * from session_status; ERROR 3167 (HY000): The 'INFORMATION_SCHEMA.SESSION_STATUS' feature is disabled; see the documentation for 'show_compatibility_56'GLOBAL_STATUS和SESSION_STATUS表提供有关服务器状态变量的信息。 它们的内容对应于SHOW GLOBAL STATUS和SHOW SESSION STATUS语句产生的信息（参见“SHOW STATUS语法”）。
INFORMATION_SCHEMA NameSHOW NameRemarksVARIABLE_NAMEVariable_nameVARIABLE_VALUEValue每个表的VARIABLE_VALUE列定义为VARCHAR（1024）。
mysql> select * from performance_schema.global_variables LIMIT 1; +--------------------------+----------------+ | VARIABLE_NAME | VARIABLE_VALUE | +--------------------------+----------------+ | auto_increment_increment | 1 | +--------------------------+----------------+ 1 row in set (0.00 sec) mysql> select * from performance_schema.session_variables limit 2; +--------------------------+----------------+ | VARIABLE_NAME | VARIABLE_VALUE | +--------------------------+----------------+ | auto_increment_increment | 1 | | auto_increment_offset | 1 | +--------------------------+----------------+ 2 rows in set (0.00 sec) mysql> show global status like 'Innodb_data_written'; +---------------------+---------+ | Variable_name | Value | +---------------------+---------+ | Innodb_data_written | 1968128 | +---------------------+---------+ 1 row in set (0.01 sec) mysql> show status like 'Innodb_data_written'; +---------------------+---------+ | Variable_name | Value | +---------------------+---------+ | Innodb_data_written | 1968128 | +---------------------+---------+ 1 row in set (0.00 sec)转载于:https://www.cnblogs.com/wanbin/p/9514640.html
