Re: empty set

On Thu, Jun 08, 2006 at 14:40:12 -0700, CG <cgg007@yahoo.com> wrote:
> PostgreSQL 8.1
> 
> I've been trying to write a SQL prepare routine. One of the challenging
> elements I'm running into is an empty set ...
> 
> "select foo from bar where foo in ? ;"
> 
> What if "?" is an set with zero elements? What is the proper value to use to
> replace "?" indicating an empty set?

Something like the following suggests you can put a subquery there that returns
0 rows. I don't think that wil work for prepared queries though; so it may not
help you.

bruno=> select * from test where test in (select 1 where false);test
------
(0 rows)