lpopa

###Short version
SELECT blocked_locks.pid     AS blocked_pid,
         blocked_activity.usename  AS blocked_user,
         blocked_activity.query    AS blocked_statement
   FROM  pg_catalog.pg_locks         blocked_locks
    JOIN pg_catalog.pg_stat_activity blocked_activity  ON blocked_activity.pid = blocked_locks.pid
  WHERE blocked_activity.query_start <= NOW() - INTERVAL '5 minutes';


####Long version