Re: date/time special values incorrectly cached as constant in plpgsql

On Sat, Oct 17, 2020 at 4:05 AM Tijs van Dam <tijs@thalex.com> wrote:

> If no change is made to the parser, then I'd propose at least a big fat
> warning in section 8.5.1.4 that 'now', 'yesterday', 'today', and 'tomorrow'
> should only be used with the greatest caution, as these values will be
> converted to constants and then cached in unexpected places.
>

IMO, there really isn't anything surprising that these literal inputs end
up converted to constants, which are indeed cached in parts of the system
that utilize a cache, or are stored as the resultant literal instead of an
expression.  That's how literal input values work.  If I need something to
be dynamic I have to use a volatile function.

I've flagged this one for later consideration and may decide to write a
documentation patch at some point - but as the existing docs aren't wrong
and do cover this dynamic, if maybe not explicitly and thoroughly enough
for some readers, the effort/benefit calculation isn't that high for me.

David J.