Re: foreign keys for array/period contains relationships

On Mon, Oct 25, 2010 at 3:11 PM, Peter Eisentraut <peter_e@gmx.net> wrote:
> Currently, foreign keys only work with the = operator (the name might be
> different, but it needs to behave like equality).  I'm thinking there
> are other scenarios that could be useful, for example with arrays and
> range types.
>
> Example #1: Foreign key side is an array, every member must match some
> PK.
>
> CREATE TABLE pk (a int PRIMARKY KEY, ...);
>
> CREATE TABLE fk (x int[] REFERENCES pk (a), ...);

I've wished for this before when doing app dev with PG.  I think it
would be pretty neat.  The other cases seem potentially useful, too,
but especially this one.

--
Robert Haas
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