Re: WIP: BRIN multi-range indexes

On Mon, 13 Jul 2020 at 09:33, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> wrote:
>
> On 2020-Jul-13, Tomas Vondra wrote:
>
> > On Sun, Jul 12, 2020 at 07:58:54PM -0400, Alvaro Herrera wrote:
>
> > > Maybe we can try to handle this with some other function that interprets
> > > the bytea in 'value' and returns a user-readable text. I think it'd
> > > have to be a superuser-only function, because otherwise you could easily
> > > cause a crash by passing a value of a different opclass. But since this
> > > seems a developer-only thing, that restriction seems fine to me.
> >
> > Ummm, I disagree a superuser check is sufficient protection from a
> > segfault or similar issues.
>
> My POV there is that it's the user's responsibility to call the right
> function; and if they fail to do so, it's their fault. I agree it's not
> ideal, but frankly these pageinspect things are not critical to get 100%
> user-friendly.
>
> > If we really want to print something nicer, I'd say it needs to be a
> > special function in the BRIN opclass.
>
> If that can be done, then +1. We just need to ensure that the function
> knows and can verify the type of index that the value comes from. I
> guess we can pass the index OID so that it can extract the opclass from
> catalogs to verify.

+1 from me, too. Perhaps we can have it as optional. If a BRIN opclass
doesn't have it, the 'values' can be null.

Regards,

--
Masahiko Sawada http://www.2ndQuadrant.com/
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