Re: Optimizer items in the release notes

On Sat, 27 Apr 2019 at 14:22, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> > > * They are hard to explain
> >
> > That can be true, but we generally get there if not the first time
> > then after a few iterations. Authors and committers of the
> > improvements are likely to be able to help find suitable wording.
>
> It is not the text that is hard, but hard to explain the concept in a
> way that relates to anything a normal user is familiar with.

Yeah, that's no doubt often going to be a struggle, but we can't
expect every person who reads the release notes to understand
everything. You could probably say the same for any internal
implementation change we make though. I don't think the planner is
unique in this regard, so I don't think it needs any special
treatment. I also don't think we need to go into great detail. The
item could be as light on detail as:

* Improve query planner's ability to push LIMIT through Sort nodes.

If you don't know what LIMIT is or what a Sort node is, then you're
probably not going to care about the change. They can keep reading on
the next line, but if the reader happens to have suffered some pain on
that during their migration attempt, then they might be quite happy to
see those words. If they want more details then they might be savvy
enough to hunt those down, or perhaps they'll come asking.

--
David Rowley http://www.2ndQuadrant.com/
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