Re: Disallow redundant indexes

> On Mon, Apr 28, 2025 at 01:12:18PM -0500, Sami Imseih wrote:
> > If I had a dollar for every time I asked a user to check for duplicate
> > indexes :) So
> > I think it's a good idea to provide some way to detect these ( besides
> > a query in the
> > Wiki ), but I don't think we should prevent it.
> >
> > While a WARNING will be a good to have, it could easily go unnoticed,
> > but it's still good to have.
>
> I don't doubt that this is a problem in the field, but I'm not sure I'm
> convinced it's worthwhile to emit a warning that only appears for exact
> duplicates and is very easily missed, not to mention that the user could be
> intentionally creating the index.
>
>
> I don't like to idea of a new GUC to control an SQL command. The WARNING seems
> fragile because it doesn't solve the problem. I also don't want to disallow
> duplicate indexes; it can break old routines. If we want to do something about
> it, I would say let's add a psql meta command or even a new view to show
> duplicate indexes. I do think that official maintenance queries are a good to
> step forward to make life easier for DBAs.

I do think adding an annotation to the index in the \d[+] psql
meta-command will be
very useful when there are indexes that are the same except for the
name (and do
not enforce constraints?). This will at least help DBAs quickly spot
such indexes in
their tables.

--
Sami