Bruce Momjian <bruce(at)momjian(dot)us> writes:
> I realize they can't be converted to constants before the query starts
> but is there a reason we can't convert those functions to constants in
> the executor before a table scan?
Other than the significant number of cycles that would be wasted (in
most cases) checking for the possibility, probably not. I'm dubious
that it would average out to a win though.
regards, tom lane