Re: Incomprehensible behaviour of a foreign key.

Just an uninformed wild guess but you seem to be in
desperate search for straws:

> create table site_membership (
>  id serial unique
>  ,group_id int references groups(id)
>  ,site_id int references someothertable(id)
>  ,primary key(site_id,group_id)
> ) without oids;

Does using id as primary key and removing the multi-key
primary key constraint on (site_id, group_id) help any ?

Unlikely but you never know...

Karsten
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