Re: Supporting = operator in gin/gist_trgm_ops

Alexander Korotkov <aekorotkov@gmail.com>

From: Alexander Korotkov <aekorotkov@gmail.com>
To: Jeff Janes <jeff.janes@gmail.com>
Cc: Georgios <gkokolatos@protonmail.com>, Julien Rouhaud <julien.rouhaud@free.fr>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2020-11-16T06:12:07Z
Lists: pgsql-hackers
On Mon, Nov 16, 2020 at 2:13 AM Jeff Janes <jeff.janes@gmail.com> wrote:
> On Sat, Nov 14, 2020 at 12:31 AM Alexander Korotkov <aekorotkov@gmail.com> wrote:
>> I went through and revised this patch.  I made the documentation
>> statement less categorical.  pg_trgm gist/gin indexes might have lower
>> performance of equality operator search than B-tree.  So, we can't
>> claim the B-tree index is always not needed.  Also, simple comparison
>> operators are <, <=, >, >=, and they are not supported.
>
> Is "simple comparison" here a well-known term of art?  If I read the doc as committed (which doesn't include the sentence above), and if I didn't already know what it was saying, I would be left wondering which comparisons those are.  Could we just say "inequality operators"?

You're right.  "Simple comparison" is vague, let's replace it with
"inequality".  Pushed, thanks!

------
Regards,
Alexander Korotkov



Commits

  1. Reword 'simple comparison' => 'inequality' in pgtrgm.sgml

  2. Add missing 'the' to pgtrgm.sgml

  3. Handle equality operator in contrib/pg_trgm