Re: Functions used in index definitions shouldn't be changed

Robert Haas wrote:
> On Thu, Nov 20, 2014 at 1:56 PM, Albe Laurenz <laurenz.albe@wien.gv.at> wrote:
> > I don't think that there is a universally compelling right or wrong to
> > questions like this, it is more a matter of taste.  Is it more important to protect
> > the casual DBA from hurting himself or herself, or is it more important to
> > provide a well honed scalpel for the experienced surgeon?
> 
> +1.
> 
> I think if we had an already-existing prohibition here and you
> proposed relaxing it, the howls would be equally loud.  We're not
> entirely consistent about how picky we are.

There is also the possibility to add syntax like this:

CREATE OR REPLACE [FORCE] FUNCTION ...

What do you think about that?  It would protect the casual user but allow
the expert to do it anyway.

Another thing I thought about is changing function volatility:
If you change the volatility of a function used in an index to anything
other than IMMUTABLE, your database will continue to work as expected, but
a dump will fail to restore with
ERROR:  functions in index expression must be marked IMMUTABLE

Is that something worth checking for?

Yours,
Laurenz Albe