Detect and Fix locked table in postgres

SELECT                                                         
    activity.pid,
    activity.usename,
    activity.query,
    blocking.pid AS blocking_id,
    blocking.query AS blocking_query
FROM pg_stat_activity AS activity
JOIN pg_stat_activity AS blocking ON blocking.pid = ANY(pg_blocking_pids(activity.pid))

SELECT pg_cancel_backend(215449), pg_terminate_backend(215449);