Re: doc: improve the restriction description of using indexes on REPLICA IDENTITY FULL table.

On Mon, Jul 24, 2023 at 12:05 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>
> On Mon, Jul 24, 2023 at 6:39 AM Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com> wrote:
> >
> > On Sat, Jul 22, 2023 at 7:32 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> > >
> > >
> > > You have moved most of the comments related to the restriction of
> > > which index can be picked atop IsIndexUsableForReplicaIdentityFull().
> > > Now, the comments related to limitation atop
> > > FindUsableIndexForReplicaIdentityFull() look slightly odd as it refers
> > > to limitations but those limitation were not stated. The comments I am
> > > referring to are: "Note that the limitations of index scans for
> > > replica identity full only .... might not be a good idea in some
> > > cases". Shall we move these as well atop
> > > IsIndexUsableForReplicaIdentityFull()?
> >
> > Good point.
> >
> > Looking at neighbor comments, the following comment looks slightly odd to me:
> >
> > * XXX: See IsIndexUsableForReplicaIdentityFull() to know the challenges in
> > * supporting indexes other than btree and hash. For partial indexes, the
> > * required changes are likely to be larger. If none of the tuples satisfy
> > * the expression for the index scan, we fall-back to sequential execution,
> > * which might not be a good idea in some cases.
> >
> > Are the first and second sentences related actually?
> >
>
> Not really.
>
> > I think we can move it as well to
> > IsIndexUsableForReplicaIdentityFull() with some adjustments. I've
> > attached the updated patch that incorporated your comment and included
> > my idea to update the comment.
> >
>
> LGTM.

Pushed.

Regards,

--
Masahiko Sawada
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