Re: Ignoring BRIN for HOT updates (was: -udpates seems broken)

On Wed, 22 Feb 2023 at 13:15, Tomas Vondra
<tomas(dot)vondra(at)enterprisedb(dot)com> wrote:
>
> On 2/20/23 19:15, Matthias van de Meent wrote:
> > Thanks. Based on feedback, attached is v2 of the patch, with as
> > significant changes:
> >
> > - We don't store the columns we mention in predicates of summarized
> > indexes in the hotblocking column anymore, they are stored in the
> > summarized columns bitmap instead. This further reduces the chance of
> > failiing to apply HOT with summarizing indexes.
>
> Interesting idea. I need to think about the correctness, but AFAICS it
> should work. Do we have any tests covering such cases?

There is a test that checks that an update to the predicated column
does update the index (on table brin_hot_2). However, the description
was out of date, so I've updated that in v4.

> > - The heaptuple header bit for summarized update in inserted tuples is
> > replaced with passing an out parameter. This simplifies the logic and
> > decreases chances of accidentally storing incorrect data.
> >
>
> OK.
>
> 0002 proposes a minor RelationGetIndexPredicate() tweak, getting rid of
> the repeated if/else branches. Feel free to discard, if you think the v2
> approach is better.

I agree that this is better, it's included in v4 of the patch, as attached.

Kind regards,

Matthias van de Meent.