2022年4月26日(火) 23:24 Laurenz Albe <laurenz.albe@xxxxxxxxxxx>: > > On Tue, 2022-04-26 at 06:59 -0700, David G. Johnston wrote: > > On Tue, Apr 26, 2022 at 6:55 AM Robert Lichtenberger <r.lichtenberger@xxxxxxxxxxx> wrote: > > > When executing "SELECT * FROM pg_stat_activity" I get lots of rows that > > > have an empty "query" column. > > > > > > According to [1] this column should contain the "Text of this backend's > > > most recent query", either a query that is currently running or the last > > > query that was executed. > > > > > > So how comes that a lot of the rows in pg_stat_activity have an empty > > > "query"? > > > > > > https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-ACTIVITY-VIEW > > > > They've never executed a query. Probably due to connection pooling opening connections for the pool but never needing to hand them out. > > An alternative option is that the last query sent was an empty string. Or it's the kind of backend which doesn't normally execute queries. epp=# SELECT backend_type FROM pg_stat_activity WHERE query = ''; backend_type ------------------------------ autovacuum launcher pglogical supervisor logical replication launcher pglogical manager 16389 background writer checkpointer walwriter (7 rows) Regards Ian Barwick -- EnterpriseDB: https://www.enterprisedb.com
