Re: [PATCH] Add support function for containment operators

On Sat, 2023-07-08 at 08:11 +0200, Kim Johan Andersson wrote:
> On 07-07-2023 13:20, Laurenz Albe wrote:
> > I wrote:
> > > You implement both "SupportRequestIndexCondition" and "SupportRequestSimplify",
> > > but when I experimented, the former was never called.  That does not
> > > surprise me, since any expression of the shape "expr <@ range constant"
> > > can be simplified.  Is the "SupportRequestIndexCondition" branch dead code?
> > > If not, do you have an example that triggers it?
>
> I would think it is dead code, I came to the same conclusion. So we can
> drop SupportRequestIndexCondition, since the simplification happens to
> take care of everything.
>
>
> > I had an idea about this:
> > So far, you only consider constant ranges.  But if we have a STABLE range
> > expression, you could use an index scan for "expr <@ range", for example
> > Index Cond (expr >= lower(range) AND expr < upper(range)).
> >
>
> I will try to look into this. Originally that was what I was hoping for,
> but didn't see way of going about it.
>
> Thanks for your comments, I will also look at the locale-related
> breakage you spotted.

I have marked the patch as "returned with feedback".

I encourage you to submit an improved version in a future commitfest!

Yours,
Laurenz Albe