blocking_activity.queryAScurrent_statement_in_blocking_processFROMpg_catalog.pg_locks blocked_locksJOINpg_catalog.pg_stat_activity blocked_activityONblocked_activity.pid=blocked_locks.pidJOINpg_catalog.pg_locks
smgr_rlocator的类型是 RelFileLocatorBackend,locator 是一个三元组,分别是<tablespaceid,database id,relation id>,backend 只对临时表有用,对普通表来说,其值一般是 -1。 在磁盘存储管理器中,其实主要就是对SMgrRelationData的管理,涉及到对其创建、打开、关闭、删除、扩展等操作。 创建表文件 在函数 mdcreate ...
开启前可以使用pg_test_timing工具来检查下开启后对性能影响,开启后IO数据会写入pg_stat_database和explain plan buffers。 以下是大量IO的示例: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 EXPLAIN(ANALYZE,BUFFERS)SELECTCOUNT(id)FROMpages;QUERYPLAN---FinalizeAggregate(cost=369672.42..369672.43rows=1wid...
[postgres@primary ~]$ psql -c "select * from pg_stat_replication;" pid | usesysid | usename | application_name | client_addr | client_hostname | client_port | backend_start | backend_xmin | state | sent_lsn | write_lsn | flush_lsn | replay_lsn | write_lag | flush_lag | repl...
```c static int ReadCommand(StringInfo inBuf) { int result; if (whereToSendOutput == DestRemote) result = SocketBackend(inBuf); else result = InteractiveBackend(inBuf); return result; } ReadCommand 从前端或标准输入读取命令,将其放入 inBuf,并返回消息类型代码(消息的第一个字节)。 如果遇到...
Please read more about our beta testing process and how you can contribute. Release Announcement Release Notes Versioning Policy Download Browse Archives Submit News pgmoneta 0.17 2025-05-26 by pgmoneta pg_ivm 1.11 released 2025-05-26 by IVM Development Group CloudNativePG 1.26.0 and ...
The underlying table pg_statistic can only be examined by the bootstrap superuser. You could GRANT your userOne way to work around this is to create a function owned by a superuser with SELECTSECURITY DEFINER rights tothat selects from pg_statisticpg_stats and use that tablereturns the resu...
安装完成之后(CREATE EXTENSION pg_cron;),可以使用如下命令定期调用存储过程: -- Create a schedule to run the procedure every hour SELECT cron.schedule('0 * * * *', $$CALL expire_rows('1 hour');$$); -- List all scheduled jobs
在base 目录下,存储了不同 Database 的数据,例如在我的当前环境中,当前的数据库名为rose,其 oid 为 24582。 img 所以在 Postgres 数据目录的 base 目录下,就会有对应的 Database 目录,目录名称就是 Oid: img 我在当前数据库中有一个表,其名为 articles,我们可以通过pg_class表查询到对应的表 relfilenode。
To be able to collect metrics from pg_stat* views as non-superuser in PostgreSQL server versions >= 10 you can grant the pg_monitor or pg_read_all_stats built-in roles to the user. If you need to monitor older PostgreSQL servers, you will have to create functions and views as a ...