Horton

Re: Collation versioning

Thomas Munro <thomas.munro@gmail.com>

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From: Thomas Munro <thomas.munro@gmail.com>
To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Cc: Christoph Berg <myon@debian.org>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-10-03T12:25:54Z
Lists: pgsql-hackers

Attachments

On Thu, Oct 3, 2019 at 7:53 AM Peter Eisentraut
<peter.eisentraut@2ndquadrant.com> wrote:
> On 2018-09-05 23:18, Thomas Munro wrote:
> > On Wed, Sep 5, 2018 at 12:10 PM Christoph Berg <myon@debian.org> wrote:
> >>> So, it's not ideal but perhaps worth considering on the grounds that
> >>> it's better than nothing?
> >>
> >> Ack.
> >
> > Ok, here's a little patch like that.
> >
> > postgres=# select collname, collcollate, collversion from pg_collation
> > where collname = 'en_NZ';
> >  collname | collcollate | collversion
> > ----------+-------------+-------------
> >  en_NZ    | en_NZ.utf8  | 2.24
> > (1 row)
>
> After, um, briefly sleeping on this, I would like to go ahead with this.
>
> There is ongoing work to make ICU available globally, and as part of
> that I've also proposed a way to make the collation version tracking
> work on a database level.
>
> This here would be a useful piece on the overall picture.  Independent
> of what becomes of the ICU effort, we could have glibc collation version
> tracking completely working for PG13.

+1

Also, better ideas about which objects to attach versions to can come
along independently of this.

> The only open question on this patch was whether it's a good version to
> use.  I think based on subsequent discussions, there was the realization
> that this is the best we can do and better than nothing.
>
> In the patch, I would skip the configure test and just do
>
> #ifdef __GLIBC__
>
> directly.

Ok.  Here's one like that.  Also, a WIP patch for FreeBSD.

Thanks,
Thomas

Commits

  1. Doc: Document known problem with Windows collation versions.

  2. Add collation versions for FreeBSD.

  3. Tolerate version lookup failure for old style Windows locale names.

  4. Track collation versions for indexes.

  5. Add pg_depend.refobjversion.

  6. Remove pg_collation.collversion.

  7. Fix the MSVC build for versions 2015 and later.

  8. Add collation versions for Windows.

  9. Implement type regcollation

  10. Use libc version as a collation version on glibc systems.

  11. Make type "name" collation-aware.