pg_stat_get_backend_activity_start() 是一个系统函数,用于报告指定后端最近一次查询的开始时间。
pg_stat_get_backend_activity_start() 添加于 PostgreSQL 7.4。
用法
pg_stat_get_backend_activity_start (integer) →timestamp with time zone
后端由 pg_stat_get_backend_idset() 报告的后端 ID 号指定;请参见下面的执行示例。
pg_stat_get_backend_activity_start() 返回的值对应于 pg_stat_activity 中的 query_start 列。
相关函数
以下相关函数也可用
pg_stat_get_backend_activity()pg_stat_get_backend_client_addr()pg_stat_get_backend_client_port()pg_stat_get_backend_dbid()pg_stat_get_backend_pid()pg_stat_get_backend_start()pg_stat_get_backend_userid()pg_stat_get_backend_wait_event()pg_stat_get_backend_wait_event_type()pg_stat_get_backend_xact_start()
变更历史
- PostgreSQL 7.4
- 新增于(提交 a1833100)
示例
pg_stat_get_backend_activity_start() 的基本执行示例
postgres=# SELECT pg_stat_get_backend_pid(s.backendid) AS pid,
pg_stat_get_backend_activity_start(s.backendid) AS query_start
FROM (SELECT pg_stat_get_backend_idset() AS backendid) AS s;
pid | query_start
-------+-------------------------------
23529 |
23532 |
18419 | 2021-07-20 04:29:24.54157+02
6177 |
18474 | 2021-07-20 04:26:35.539942+02
18427 | 2021-07-20 04:29:23.355595+02
18488 | 2021-07-20 04:27:18.906881+02
18185 | 2021-07-20 04:21:58.292271+02
16549 | 2021-07-20 03:38:12.636572+02
18489 | 2021-07-20 04:29:23.968442+02
18546 | 2021-07-20 04:29:26.69587+02
18359 | 2021-07-20 04:27:32.220973+02
18362 | 2021-07-20 04:29:06.522822+02
6233 |
18566 | 2021-07-20 04:29:49.440485+02
23527 |
23526 |
23528 |
(18 rows)
参考资料
- PostgreSQL 文档: 后端统计信息函数
