show_compatibility_56

--从mysql5.7.6开始information_schema.global_status已经开始被舍弃，为了兼容性，此时需要打开 show_compatibility_56
mysql> select * from information_schema.global_status limit 3;
ERROR 3167 (HY000): The 'INFORMATION_SCHEMA.GLOBAL_STATUS' feature is disabled; see the documentation for 'show_compatibility_56'

--查看show_compatibility_56其值
mysql> show variables like '%show_compatibility_56%';
+-----------------------+-------+
| Variable_name         | Value |
+-----------------------+-------+
| show_compatibility_56 | OFF   |
+-----------------------+-------+
1 row in set (0.01 sec)

--把show_compatibility_56打开
mysql> set global show_compatibility_56=on;
Query OK, 0 rows affected (0.00 sec)

mysql> show variables like '%show_compatibility_56%';
+-----------------------+-------+
| Variable_name         | Value |
+-----------------------+-------+
| show_compatibility_56 | ON    |
+-----------------------+-------+
1 row in set (0.00 sec)

mysql> select * from information_schema.global_status limit 3;
+-----------------------+----------------+
| VARIABLE_NAME         | VARIABLE_VALUE |
+-----------------------+----------------+
| ABORTED_CLIENTS       | 0              |
| ABORTED_CONNECTS      | 0              |
| BINLOG_CACHE_DISK_USE | 0              |
+-----------------------+----------------+
3 rows in set, 1 warning (0.00 sec)

In MySQL 5.6, system and status variable information is available from these SHOW statements:

SHOW VARIABLES
SHOW STATUS
And from these INFORMATION_SCHEMA tables:
INFORMATION_SCHEMA.GLOBAL_VARIABLES
INFORMATION_SCHEMA.SESSION_VARIABLES
INFORMATION_SCHEMA.GLOBAL_STATUS
INFORMATION_SCHEMA.SESSION_STATUS

MySQL 5.7
As of MySQL 5.7.6, the Performance Schema includes these tables as new sources of system and status
variable information:
performance_schema.global_variables
performance_schema.session_variables
performance_schema.variables_by_thread
performance_schema.global_status
performance_schema.session_status
performance_schema.status_by_thread
performance_schema.status_by_account
performance_schema.status_by_host
performance_schema.status_by_user