On 1 March 2016 at 17:22, Jeff Janes <jeff.ja...@gmail.com> wrote:
> On Tue, Mar 1, 2016 at 7:40 AM, Tom Lane <t...@sss.pgh.pa.us> wrote:
> > Tobias Florek <postg...@ibotty.net> writes:
> >> When creating an index to use for an ORDER BY clause, a simple query
> >> starts to return more results than expected. See the following detailed
> >> log.
> > Ugh. That is *badly* broken. I thought maybe it had something to do
> > the "abbreviated keys" work, but the same thing happens if you change the
> > numeric column to integer, so I'm not very sure where to look. Who's
> > touched btree key comparison logic lately?
> > (Problem is reproducible in 9.5 and HEAD, but not 9.4.)
> Bisects down to:
> 606c0123d627b37d5ac3f7c2c97cd715dde7842f is the first bad commit
> commit 606c0123d627b37d5ac3f7c2c97cd715dde7842f
> Author: Simon Riggs <si...@2ndquadrant.com>
> Date: Tue Nov 18 10:24:55 2014 +0000
> Reduce btree scan overhead for < and > strategies
> For <, <=, > and >= strategies, mark the first scan key
> as already matched if scanning in an appropriate direction.
> If index tuple contains no nulls we can skip the first
> re-check for each tuple.
> Author: Rajeev Rastogi
> Reviewer: Haribabu Kommi
> Rework of the code and comments by Simon Riggs
Looks like we'll need a new release as soon as we can lock down a fix.
Simon Riggs http://www.2ndQuadrant.com/
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