Re: Need for re-index after pg_upgrade

På mandag 29. juni 2015 kl. 15:42:22, skrev Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us
<mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us>>:
Andreas Joseph Krogh <andreas(at)visena(dot)com> writes:
> In the man-page for pg_upgrade we see this:
> pg_upgrade will require a reindex if:
>  * an index is of type hash or GIN

I think that probably refers to some version-specific upgrade
situations; I can't see a reason why it would be true in general.
Bruce, doesn't that doc need improvement?

regards, tom lane
 
I'm specifically thinking about this (from 9.4 release-notes):
E.5.3.1.1. Indexes <>

* Reduce GIN <http://www.postgresql.org/docs/9.4/static/gin.html> index size
(Alexander Korotkov, Heikki Linnakangas)

Indexes upgraded via pg_upgrade
<http://www.postgresql.org/docs/9.4/static/pgupgrade.html> will work fine but
will still be in the old, largerGIN format. Use REINDEX
<http://www.postgresql.org/docs/9.4/static/sql-reindex.html> to recreate old
GIN indexes in the new format.

 
It'd be great if pg_upgrade generated re-index scripts to make those indexes
use the new format.
 
-- Andreas Joseph Krogh
CTO / Partner - Visena AS
Mobile: +47 909 56 963
andreas(at)visena(dot)com <mailto:andreas(at)visena(dot)com>
www.visena.com <https://www.visena.com>
<https://www.visena.com>