Re: [HACKERS] PC Week Labs benchmark results

At 04:38 AM 2/4/00 -0500, Mike Mascari wrote:

>That's always been annoying, although it can be simulated
>easily with:
>
>SELECT t1.x, t2.y 
>FROM t1, t2
>WHERE t1.x = t2.x
>UNION
>SELECT t1.x, NULL
>FROM t1 WHERE NOT EXISTS ( SELECT t2.x FROM t2 WHERE t1.x =
>t2.x );

SOME - but not all - outer joins can be simulated with this
trick.  Others require subselects in the target list, etc.

And the union form gets really messy when a query includes more
than one outer join.




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