Re: [PATCHES] extension for sql update

On Mon, 2006-07-31 at 17:26 +0200, Peter Eisentraut wrote:
> Am Mittwoch, 26. Juli 2006 22:58 schrieb Tom Lane:
> > The reason people want this syntax is that they expect to be
> > able to write, say,
> >
> > 	UPDATE mytab SET (foo, bar, baz) =
> > 	    (SELECT alpha, beta, gamma FROM othertab WHERE key = mytab.key);
> 
> I don't find any derivation in the standard that would permit this.  The only 
> thing I could find are variations on
> 
> SET (a) = x  -- no parentheses
> SET (a, b) = (x, y)
> SET (a, b) = ROW (x, y)
> 
> where x and y are some sort of value expression.  I would have expected the 
> sort of thing that you describe, but if you know how to derive that, I'd like 
> to see it.

I believe  can be
one or more  which includes a .
 gives us the  option.

For that matter the below portion of  gives us: |  
    

This breaks down into one or more comma separated s.

UPDATE tab SET (...) = ((SELECT foo, bar from a), (select bif,baz from
b));

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