Re: [PATCH] Support for Array ELEMENT Foreign Keys

On Friday, October 19, 2012 09:55:10 PM Tom Lane wrote:
>         FOREIGN KEY (foo, EACH ELEMENT OF bar) REFERENCES ...
> 
> which is certainly more verbose than just "ELEMENT" but I think it
> makes it clearer that each array element is required to have a match
> separately.  If we ever implemented the other behavior it could be
> written as "ANY ELEMENT OF".
> 
> That doesn't get us any closer to having a working column-constraint
> syntax unfortunately, because EACH is not a reserved word either
> so "EACH ELEMENT REFERENCES" still isn't gonna work.  I'm getting
> more willing to give up on having a column-constraint form of this.

What about sticking a WHERE in there? I.e. FOREIGN KEY (foo, WHERE EACH 
ELEMENT OF bar) ...

Greetings,

Andres
-- 
Andres Freund        http://www.2ndQuadrant.com/
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