Re: Replace IN VALUES with ANY in WHERE clauses during optimization

On Thu, 2024-10-03 at 23:10 +0300, Alena Rybakina wrote:
> On 03.10.2024 22:52, Ivan Kush wrote:
> >
> > Hello, hackers! I with my friends propose the patch to replace IN
> > VALUES to ANY in WHERE clauses.
> >
> > # Intro
> >
> > The `VALUES` in the `IN VALUES` construct is replaced with with an
> > array of values when `VALUES` contains 1 column. In the end it will be
> > replaced with ANY by the existing function makeA_Expr
> > (src/backend/nodes/makefuncs.c)
> >
> > This improves performance, especially if the values are small.
>
> Anlrey Lepikhov and I recently described this in an article [0] here and
> the implementation already exists, but for now it was posted a binary
> application for testing. The acceleration is significant I agree.
>
> [0] https://danolivo.substack.com/p/7456653e-9716-4e91-ad09-83737784c665

I believe that the speed improvement is significant, but who writes a
query like

... WHERE col IN (VALUES (1), (2), (3))

when they could write the much shorter

... WHERE col IN (1, 2, 3)

which is already converted to "= ANY"?

I wonder if it is worth the extra planning time to detect and improve
such queries.

Yours,
Laurenz Albe