Re: MULTISET and additional functions for ARRAY

On fre, 2010-11-12 at 09:44 -0500, Tom Lane wrote:
> But I'm still not convinced that this feature is useful enough to
> justify the implementation effort.  AFAICS there's nothing here that
> you couldn't get with some non-default operators on regular arrays,

Unique constraints would behave differently for arrays and multisets.
But I suppose you could get something similar with exclusion constraints
nowadays.  But not for primary keys.

Foreign keys also don't work easily with nondefault operators.

JOIN / USING doesn't work.

ORDER BY would work but look ugly.  And such coding where you'd have to
remember the nondefault operator everywhere would also be error prone.