Re: More on inheritance and foreign keys

Tom Lane wrote:
> "Zeugswetter Andreas DCP SD" <ZeugswetterA(at)spardat(dot)at> writes:
>
>>>The solution to the foreign key problem seems easy if I
>>>modify PostgreSQL implementation and take off the ONLY word
>>>from the SELECT query, but it's not an option for me, as I'm
>
>
>>I think that the ONLY was wrong from day one :-(
>
>
> Well, sure, but until we have an implementation that actually *works*
> across multiple tables, it has to be there so that we can at least
> consistently support the current single-table semantics. Until we
> have some form of cross-table unique constraint (index or whatever)

I managed uniqueness using normal indexes and ins/upd triggers on all
child tables:

CREATE OR REPLACE FUNCTION checkchildsunique
RETURNS trigger AS
$BODY$BEGIN
IF EXISTS (
SELECT 1 FROM foo Master
WHERE Master.primaryKeyCol = NEW.primaryKeyCol)
THEN
RAISE EXCEPTION 'Primary Key violation in table % on %',
TG_RELNAME, TG_OP;
END IF;
RETURN NEW;
END;$BODY$ LANGUAGE 'plpgsql'

Shouldn't be too complicated to implement it as internal function.

Regards,
Andreas