MySQL 5.7
可以通过global status
group_replication_primary_member
确定
root@db20:59: [mgr]> SELECT VARIABLE_VALUE
-> FROM performance_schema.global_status
-> WHERE VARIABLE_NAME = 'group_replication_primary_member';
+--------------------------------------+
| VARIABLE_VALUE |
+--------------------------------------+
| f8da6826-328a-11e9-8e54-000c29d7ca48 |
+--------------------------------------+
1 row in set (0.00 sec)
可以结合 performance_schema.replication_group_members 表 获取主机名和端口信息:
root@db21:05: [mgr]> SELECT
-> MEMBER_HOST, MEMBER_PORT
-> FROM
-> performance_schema.replication_group_members
-> WHERE
-> MEMBER_ID = (SELECT
-> VARIABLE_VALUE
-> FROM
-> performance_schema.global_status
-> WHERE
-> VARIABLE_NAME = 'group_replication_primary_member');
+-------------+-------------+
| MEMBER_HOST | MEMBER_PORT |
+-------------+-------------+
| mgr1 | 3306 |
+-------------+-------------+
1 row in set (0.00 sec)
或者获取全部成员信息:
root@db21:05: [mgr]> SELECT
-> MEMBER_ID,
-> MEMBER_HOST,
-> MEMBER_PORT,
-> MEMBER_STATE,
-> IF(global_status.VARIABLE_NAME IS NOT NULL,
-> 'PRIMARY',
-> 'SECONDARY') AS MEMBER_ROLE
-> FROM
-> performance_schema.replication_group_members
-> LEFT JOIN
-> performance_schema.global_status ON global_status.VARIABLE_NAME = 'group_replication_primary_member'
-> AND global_status.VARIABLE_VALUE = replication_group_members.MEMBER_ID;
+--------------------------------------+-------------+-------------+--------------+-------------+
| MEMBER_ID | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | MEMBER_ROLE |
+--------------------------------------+-------------+-------------+--------------+-------------+
| f8da6826-328a-11e9-8e54-000c29d7ca48 | mgr1 | 3306 | ONLINE | PRIMARY |
| 030930d7-32b2-11e9-8298-000c292aafc5 | mgr2 | 3306 | ONLINE | SECONDARY |
| 202bdcd5-32b3-11e9-9f4f-000c29322d33 | mgr3 | 3306 | ONLINE | SECONDARY |
+--------------------------------------+-------------+-------------+--------------+-------------+
3 rows in set (0.01 sec)
MySQL 8.0.2 and Later
MySQL 8.0.2开始, Performance Schema被扩展
SELECT MEMBER_HOST, MEMBER_PORT FROM performance_schema.replication_group_members WHERE MEMBER_ROLE = 'PRIMARY';
或者获取全部成员信息:
mysql> SELECT MEMBER_ID, MEMBER_HOST, MEMBER_PORT, MEMBER_STATE, MEMBER_ROLE, MEMBER_VERSION FROM performance_schema.replication_group_members;
