Re: PostgreSQL 12: Feature Highlights

On Wed, May 15, 2019 at 05:36:32PM +0900, Amit Langote wrote:
> Hi David,
>
> On 2019/05/15 11:59, David Rowley wrote:
> > Sadly, they can't refer to the release notes for more information
> > since they don't detail what's changed in this area :(
>
> Bruce seemed to insist on summarizing all the performance-related
> improvements into one item. Initial wording mentioned just pruning, which
> after some back and forth has finally been turned into:
>
> Improve performance of many operations on partitioned tables
> (Amit Langote, David Rowley, Tom Lane, Álvaro Herrera)
>
> Tables with thousands of child partitions can now be processed
> efficiently by operations that only need to touch a small number of
> partitions.
>
> I hear you saying that the description may be too vague *for release
> notes* even though it now covers *all* the performance improvements made
> to address the use cases where small number of partitions are touched.
> Maybe, you're saying that we should've mentioned individual items
> (partition pruning, tuple routing, etc.) at least in the release notes,
> which I did suggest on -committers [1], but maybe Bruce didn't think it
> was necessary to list up individual items.
>
> That leaves a few other commits mentioned in the release-12.sgml next to
> this item that are really not related to this headline description, which
> both you and I have pointed out in different threads [2][3], but I haven't
> really caught Bruce's position about them.

I think the more specific we make the partition description, the more
limited it will appear to be. I think almost all partition operations
will appear to be faster with PG 12, even if users can't articulate
exactly why.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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