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慢SQL分析

数据仓库服务 GAUSSDB(DWS)-分析作业是否被阻塞:操作步骤

操作步骤查看阻塞的查询语句及阻塞查询的表、模式信息。 1 2 3 4 5 6 7 8 9 10 11 SELECT w.query as waiting_query, w.pid as w_pid, w.usename as w_user, l.query as locking_query, l.pid as l_pid, l.usename as l_user, t.schemaname || '.' || t.relname as tablename from pg_stat_activity w join pg_locks l1 on w.pid = l1.pid and not l1.granted join pg_locks l2 on l1.relation = l2.relation and l2.granted join pg_stat_activity l on l2.pid = l.pid join pg_stat_user_tables t on l1.relation = t.relid where w.waiting; 该查询返回线程ID、用户信息、查询状态，以及导致阻塞的表、模式信息。使用如下命令结束相应的会话。其中，139834762094352为线程ID。 1 SELECT PG_TERMINATE_BACKEND(139834762094352); 显示类似如下信息，表示结束会话成功。 PG_TERMINATE_BACKEND ---------------------- t (1 row) 显示类似如下信息，表示用户正在尝试结束当前会话，此时仅会重连会话，而不是结束会话。 FATAL: terminating connection due to administrator command FATAL: terminating connection due to administrator command The connection to the server was lost. Attempting reset: Succeeded. gsql客户端使用PG_TERMINATE_BACKEND函数终止本会话后台线程时，客户端不会退出而是自动重连。

数据仓库服务 GAUSSDB(DWS) 慢SQL分析