Re: Re: Missing rows with index scan when collation is not "C" (PostgreSQL 9.5)

On Wed, Mar 23, 2016 at 7:06 PM, Peter Geoghegan <pg(at)heroku(dot)com> wrote:

> On Wed, Mar 23, 2016 at 11:04 AM, Magnus Hagander <magnus(at)hagander(dot)net>
> wrote:
> > That said, my main point is that I do not think the knob is something
> that
> > should be tuned by the average end user. For most people, that should be
> > left to the packagers for the platform, who can make an informed choice
> > about if it's safe to turn it on.
>
> I could get behind that if we really make an effort to help them make
> an informed choice. The abbreviated keys optimization is highly
> valuable, and I put a lot of work into it, as did Robert.
>

Oh, I totally appreciate that. It's one of the great improvements in 9.5,
and one of the best things is that it's an "automatic improvement" that
doesn't require the users to change their applications to benefit from it.
But it's also currently badly broken on some of our most common platforms.

We want to get it back to working. But short-term, it's more important to
limit the scope of the brokenness, since this is a version that people are
putting in production. Once we have enough info to safely say we've put a
workaround in place, we turn it back on.

--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/