PostgresSQL Get number of connection connected to server

之前 個Website down 之後發現原來係 PostgresSQL connection 爆左.. 所以個server 唔可以再make connection…
想知道個SQL D connection 用左幾多…

Stackoverflow 完之後搵到一個 PSQL 既 query, 可以用黎 check 下用緊幾多connection
同仲有幾多connection remain


select max_conn,used,res_for_super,max_conn-used-res_for_super res_for_normal 
  (select count(*) used from pg_stat_activity) t1,
  (select setting::int res_for_super from pg_settings where name=$$superuser_reserved_connections$$) t2,
  (select setting::int max_conn from pg_settings where name=$$max_connections$$) t3

hope you find it useful

Chi Yau
Chi Yau
Software Engineer

Interested on Learning new stuff and experience sharing