postgresql 如何检查热备是否提供只读查询
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How to check if hot standby serves read-only queries
提问by Alexander
I have setup replication: master - slave. Slave server works as hot-standby, which means we can run read-only sql queries. How actually can I see that slave server is serving read-only queries?
我已经设置复制：主 - 从。从服务器作为热备工作，这意味着我们可以运行只读 sql 查询。我如何才能看到从服务器正在提供只读查询？
回答by yoloseem
You can use pg_is_in_recovery()which returns Trueif recovery is still in progress(so the server is running in standby mode). Check the System Administration Functionsfor further informations.
如果恢复仍在进行中pg_is_in_recovery()，您可以使用which 返回True（因此服务器在待机模式下运行）。检查系统管理功能以获取更多信息。
=# SELECT pg_is_in_recovery();
pg_is_in_recovery
───────────────────
f
(1 row)
