Re: IMMUTABLE and PARALLEL SAFE function markings

Greetings,

* Andres Freund (andres@anarazel.de) wrote:
> On 2018-11-26 19:05:02 -0500, Stephen Frost wrote:
> > Agreed, but I could see us having a regression test which complains if
> > it finds any which are marked as immutable but aren't parallel safe.
>
> That doesn't help if a user writes a query to review the not parallel
> safe functions in their installation.

I'm really not sure what you're getting at here..?

Parallel safe functions should be marked as such.  Immutable functions
should be marked as such.  We should not assume that one implies the
other, nor should we operate as if they do.

My suggestion for a regression test was to make PG developers really
think about if their new immutable functions should also be marked as
parallel safe, in the event that they forget to mark it as such.  If
it's really immutable and not parallel safe, then they need to adjust
the expected regression test output (and we can all see it...).

Thanks!

Stephen