Was looking for a method of getting queries that are running longer than 5 minutes out of a PostgreSQL. This solution needs stats_command_string enabled in the postgresql.conf, though. The query you can run:
echo "select procpid,datname,current_query,now() - pg_stat_activity.query_start as duration from pg_stat_activity where pg_stat_activity.current_query <> '
Hope this helps someone!