ohp@pyrenet.fr writes:
> All triggers in the schema are named. So I assume they are triggers for
> foreign keys.
No, foreign-key triggers always have names too, and they don't look like
that (they look like RI_ConstraintTrigger_nnn). I cannot find anyplace
in PG that supplies "<unnamed>" as a default name for a trigger, either.
So there's something weird about your schema, and we really need to
see a test case ...
regards, tom lane