Re: Declaring a strict function returns not null / eval speed

Re: Tom Lane 2019-10-22 <821.1571771210@sss.pgh.pa.us>
> Actually, I think we probably don't need any SQL representation of this
> at all, because if what you're going to do with it is omit logically
> necessary null-value checks, then a wrong setting would trivially crash
> the server.  Therefore, we can never give the ability to set this flag
> to users; we could only set it on built-in functions.

Or require superuser.

> This doesn't seem too awful to me, because non-builtin functions are
> most likely slow enough that it doesn't matter.

Some years ago, Kohsuke Kawaguchi, the Jenkins author, was giving a
keynote at FOSDEM about extensibility of software. The gist I took
away from it was the tagline "if core can do something that extensions
can't, that's a bug". I think that's something that PostgreSQL should
try to live up to as well.

Christoph