А причем тут джанго? Базы же разные могут быть.
В постгресе:
SELECT
pid, rank() OVER (PARTITION BY client_addr ORDER BY backend_start) AS rank
FROM
pg_stat_activity
WHERE pid <> pg_backend_pid( )
AND application_name !~ '(?:psql)|(?:pgAdmin.+)'
AND datname = current_database()
AND state in ('idle', 'idle in transaction', 'idle in transaction (aborted)', 'disabled')
AND current_timestamp - state_change > interval '30 minutes'