Re: 9.5: UPDATE/DELETE .. ORDER BY .. LIMIT ..

On Sun, May 11, 2014 at 12:47 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
>> On 11 May 2014 11:18, Andres Freund <andres@2ndquadrant.com> wrote:
>>> I don't know. I'd find UPDATE/DELETE ORDER BY something rather
>>> useful.
>
>> Perhaps if an index exists to provide an ordering that makes it clear
>> what this means, then yes.
>
> The $64 question is whether we'd accept an implementation that fails
> if the target table has children (ie, is partitioned).

I'd say "no".  Partitioning is important, and we need to make it more
seamless and better-integrated, not add new warts.

> That seems
> to me to not be up to the project's usual quality expectations, but
> maybe if there's enough demand for a partial solution we should do so.

I like this feature, but if I were searching for places where it makes
sense to loosen our project's usual quality expectations, this isn't
where I'd start.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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