Re: pg_stat_statements and "IN" conditions

On Tue, 31 Oct 2023 at 14:36, Dmitry Dolgov <9erthalion6(at)gmail(dot)com> wrote:
>
> > On Fri, Oct 27, 2023 at 05:02:44PM +0200, Dmitry Dolgov wrote:
> > > On Thu, Oct 26, 2023 at 09:08:42AM +0900, Michael Paquier wrote:
> > > typedef struct ArrayExpr
> > > {
> > > + pg_node_attr(custom_query_jumble)
> > > +
> > >
> > > Hmm. I am not sure that this is the best approach
> > > implementation-wise. Wouldn't it be better to invent a new
> > > pg_node_attr (these can include parameters as well!), say
> > > query_jumble_merge or query_jumble_agg_location that aggregates all
> > > the parameters of a list to be considered as a single element. To put
> > > it short, we could also apply the same property to other parts of a
> > > parsed tree, and not only an ArrayExpr's list.
> >
> > Sounds like an interesting idea, something like:
> >
> > typedef struct ArrayExpr
> > {
> > ...
> > List *elements pg_node_attr(query_jumble_merge);
> >
> > to replace simple JUMBLE_NODE(elements) with more elaborated logic.
> >
> > > /* GUC parameters */
> > > extern PGDLLIMPORT int compute_query_id;
> > > -
> > > +extern PGDLLIMPORT bool query_id_const_merge;
> > >
> > > Not much a fan of this addition as well for an in-core GUC. I would
> > > suggest pushing the GUC layer to pg_stat_statements, maintaining the
> > > computation method to use as a field of JumbleState as I suspect that
> > > this is something we should not enforce system-wide, but at
> > > extension-level instead.
> >
> > I also do not particularly like an extra GUC here, but as far as I can
> > tell to make it pg_stat_statements GUC only it has to be something
> > similar to EnableQueryId (e.g. EnableQueryConstMerging), that will be
> > called from pgss. Does this sound better?
>
> For clarity, here is what I had in mind for those two points.

CFBot shows documentation build has failed at [1] with:
[07:44:55.531] time make -s -j${BUILD_JOBS} -C doc
[07:44:57.987] postgres.sgml:572: element xref: validity error : IDREF
attribute linkend references an unknown ID
"guc-query-id-const-merge-threshold"
[07:44:58.179] make[2]: *** [Makefile:70: postgres-full.xml] Error 4
[07:44:58.179] make[2]: *** Deleting file 'postgres-full.xml'
[07:44:58.181] make[1]: *** [Makefile:8: all] Error 2
[07:44:58.182] make: *** [Makefile:16: all] Error 2

[1] - https://cirrus-ci.com/task/6688578378399744

Regards,
Vignesh