Re: Rows violating Foreign key constraint exists

Nandakumar M <m(dot)nanda92(at)gmail(dot)com> writes:
>> It could be that somebody disabled the triggers, but that would have to
>> be a superuser. And I hope that people randomly disabling system triggers
>> on tables don't have superuser access to your database.

> It is unlikely that this happened. So I am assuming corruption.
> But I am able to query both the referred and referring table
> successfully without any 'missing chunk' or similar errors that
> usually indicate corruption.
> Is it possible that corruption might cause data loss like this without
> any errors?

The most likely "corruption" explanation is something wrong with the
indexes on the referenced and/or referencing column, causing rows to
not be found when referential actions should have found them. Random
querying of the tables wouldn't necessarily expose that --- you'd need
to be sure that your queries use the questionable indexes, and maybe
even search for some of the specific rows that seem mis-indexed.

regards, tom lane