Re: Deprecating Hash Indexes

On 15 October 2012 15:13, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Sun, Oct 14, 2012 at 9:45 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>> * Put WARNINGs in the docs against the use of hash indexes, backpatch
>> to 8.3. CREATE INDEX gives no warning currently, though Index Types
>> does mention a caution.
>
> I'd be in favor of adding such warnings to the documentation if they
> are not there already, and possibly even warning on CREATE INDEX ..
> USING hash().

Sounds like a good idea.

> I don't think I'd go so far as to say that we should
> imply that they'll be removed in a future release. Given how deeply
> intertwined they are with the planner, I doubt that that will happen;
> and I think there is enough interest in the technology that it's
> likely to eventually be fixed.

Hash indexes aren't used in the planner. Hash joins use completely
separate code.

--
Simon Riggs http://www.2ndQuadrant.com/
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