Re: Invisible Indexes

On 2018-06-18 18:05:11 -0400, Tom Lane wrote:
> Andres Freund <andres(at)anarazel(dot)de> writes:
> > On 2018-06-18 17:57:04 -0400, Tom Lane wrote:
> >> I think the actually desirable way to handle this sort of thing is through
> >> an "index advisor" sort of plugin, which can hide a given index from the
> >> planner without any globally visible side-effects.
>
> > Although I'm a bit doubtful that just shoving this into an extension is
> > really sufficient. This is an extremely common task.
>
> Well, what I was thinking about was that this functionality already
> exists (I think) in one or more "index advisor" plugins.

They're doing the opposite, right? I.e. they return "hypothetical
indexes", which then can be used by the planner. None of the ones I've
seen currently mask out an existing index.

> It's possible that they've all bit-rotted for lack of support, which
> would not speak highly of the demand for the feature.

IDK, the DBA / developer crowd hitting issues like this isn't the same
as the crowd willing to update an external plugin that doesn't even do
quite what you want, and was more experimental than anything.

Greetings,

Andres Freund