PostgreSQL查询会话连接数

一、查看所有连接

select * -- datname,pid,application_name,state 
from pg_stat_activity;

二、查询最大连接数

select max_conn-now_conn as resi_conn from (select setting::int8 as max_conn,(select count(*) from pg_stat_activity) as now_conn from pg_settings where name = 'max_connections') t;
show max_connections; -- 192

三、查询超级用户连接数

show superuser_reserved_connections;

四、杀掉空闲进程

select 'select pg_terminate_backend('||pid||');' as terminate_script
      ,datname,pid,application_name,state,client_addr,query
from pg_stat_activity
where state = 'idle'
and usename = 'tzq'
order by client_addr;