MGR變量group_replication_primary

組復(fù)制的狀態(tài)變量只有一個(gè)，目前在8.0.17這個(gè)版本上還是存在的，未來會(huì)被廢棄掉，我們?cè)趩沃鞯哪Ｊ较?，可以用來查看哪個(gè)節(jié)點(diǎn)是讀寫節(jié)點(diǎn)。

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mysql> show status like 'group_replication_primary_member';
+----------------------------------+--------------------------------------+
| Variable_name                    | Value                                |
+----------------------------------+--------------------------------------+
| group_replication_primary_member | 1fb894d8-e752-11e9-a0a1-00505687032a |
+----------------------------------+--------------------------------------+
1 row in set (0.00 sec)

group_replication_primary_member

Shows the primary member's UUID when the group is operating in single-primary mode. If the group is operating in multi-primary mode, shows an empty string.

The group_replication_primary_member status variable has been deprecated and is scheduled to be removed in a future version.