SQL

postgresql stop all connections

SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE pid <> pg_backend_pid() AND datname = 'db_name';

how to stop all connections to a psql 12 database?

# Works for psql 12
select pg_terminate_backend(pid) from pg_stat_activity where datname='<db_name>';

postgres kill all connections

SELECT 
    pg_terminate_backend(pid) 
FROM 
    pg_stat_activity 
WHERE 
    pid <> pg_backend_pid()
    AND datname = 'database_name';