Sam Mason <sam@samason.me.uk> wrote:
> you were requiring the types of literals that happened to be
> enclosed in quotes to have their type ascribed, so why not the NULL
> literal?
Well, unless things have changed in recent versions of the standard
and I've missed the change, a series of characters enclosed in
apostrophes is what the standard calls a "character string literal"
and defines it to be be related to character based types such as
varchar. As far as I'm aware, considering it to be undefined is a
PostgreSQL extension. If you can point to something in the standard
to show where I'm mistaken, I'll look it over. I'll go looking for
something to back my memories on the topic, too, since my memory seems
to be less reliable than it once was.....
-Kevin