On Wed, Oct 28, 2020 at 4:35 PM Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote: > > I don't think anyone proposed to do this through autovacuum. There was a > reference to auto-analyze but I think that was meant as 'run analyze > automatically.' Which would work in transactions just fine, I think. >
Maybe I was not very clear at the beginning so will try to clarify my thoughts:
1) We should add notes on our docs about the need to issue ANALYZE after creating indexes using expressions and create extended statistics. Nikolay sent a patch upthread and we can work on it and back patch.
2) REINDEX CONCURRENTLY does not keep statistics (pg_statistc) like a regular REINDEX for indexes using expressions and to me it's a bug. Michael pointed out upthread that maybe we should rework a bit index_concurrently_swap() to copy statistics from old index to new one.
> But I agree it'd likely be a more complicated patch than it might seem
> at first glance. >
If we think about a way to kick AutoAnalyze for sure it will be a more complicated task but IMHO for now we can do it simply just by copying statistics like I mentioned above.
Regards,
-- Fabrízio de Royes Mello Timbira - http://www.timbira.com.br/ PostgreSQL: Consultoria, Desenvolvimento, Suporte 24x7 e Treinamento
