Re: small exclusion constraints patch

On Sat, May 29, 2010 at 6:11 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> The only disadvantage I see of just documenting this is that someone
>> might write a user-defined index opclass that works like this, and
>> they won't be able to use this until at least 9.1 (or at least, not
>> without patching the source).
>
> I don't actually think that anyone's very likely to write a <>-like index
> operator.  It's approximately useless to use an index for such a query.
>
> Or, to put it differently: if nobody's done that in the past twenty
> years, why is it likely to happen before 9.1?

Hmm.  Well suppose we bet a dollar on whether that will happen or not.
 In fact, if you promise not to read
http://archives.postgresql.org/pgsql-hackers/2010-05/msg01175.php I'll
make it two dollars.

-- 
Robert Haas
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