Re: BUG #18244: Corruption in indexes involving whole-row expressions

On Thu, Dec 14, 2023 at 1:43 PM Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at> wrote:
>
> On Tue, 2023-12-12 at 23:04 -0500, Tom Lane wrote:
> > Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at> writes:
> > > Should we forbid composite types in index declarations? Sounds posssible,
> > > but very restrictive.
> >
> > That would make a lot of people very sad, I fear.
> >
> > I think a minimum answer could be to document that you might need to
> > REINDEX such indexes after a change in the composite type. We could
> > perhaps try to be more proactive, say by marking such indexes invalid.
> > I think though that that would have deadlock problems as well as race
> > conditions. Perhaps best to leave it at "reindex when necessary",
> > especially in view of the tiny number of reports to date.
>
> I agree. How about the attached documentation patch?
>
+ While you can use composite types in column definitions, there is usually no
+ benefit in doing so.

Is this true? If yes, we'd better update this to
https://wiki.postgresql.org/wiki/Don%27t_Do_This.

> Yours,
> Laurenz Albe

--
Regards
Junwang Zhao