Re: WIP: BRIN multi-range indexes

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.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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