If we all reacted the same way, we'd be predictable, and there's always more than one way to view a situation. What's true for the group is also true for the individual. It's simple: overspecialize, and you breed in weakness. It's slow death.
-- Ghost in the shell
UPDATE pg_class target SET reltriggers = (SELECT count(pg_trigger) FROM pg_class LEFT JOIN pg_trigger ON(pg_class.oid = pg_trigger.tgrelid) WHERE pg_class.oid = target.oid group by pg_class.oid);