On Mon, Jun 18, 2018 at 2:57 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Admittedly, this isn't great in a production environment, but neither
> would be disabling the index in the way you suggest.
>
> 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.
The globally visible side-effects are the point, though. Some users
desire cheap insurance against dropping what turns out to be the wrong
index.
FWIW, this isn't just a MySQL feature. Oracle has a similar feature.
--
Peter Geoghegan