Re: Immutable function WAY slower than Stable function?

Ken Tanzer  writes:
> Hi Adrian.  Happy to provide this info.  Though on a side note, I don't
> understand why it should matter, if functions are black box optimization
> fences.

They aren't, at least not when they are SQL-language functions that
meet the conditions for inlining.  The reason that EXPLAIN VERBOSE
is helpful here is that you can see whether the function got inlined
or not: do you see a call to the function, or a representation of
its body?

			regards, tom lane