Re: predefined functions

Rafal Pietrak <rafal(at)poczta(dot)homelinux(dot)com> writes:
> Is there a reason why both:
> SELECT current_user;
> SELECT current_database();
> are correct, while neither of:
> SELECT current_user(); -- syntax at '('
> SELECT current_database; -- missing column
> is?

Yeah: current_user (without the parens) is specified by the SQL
standard, but we're not about to adopt such a brain-dead syntax
for any of the functions defined by Postgres itself --- as you
can see from the error messages, allowing a function to be called
without parens creates a word that can't be used as a column name.
So if current_database could be called without parens, we'd actually
be violating the SQL spec by reserving a word that's not reserved
per spec.

Consistency is not one of the hallmarks of the SQL standard :-(

regards, tom lane