On Wed, May 26, 2004 at 13:57:37 -0400,
Vic Ricker <vicricker(at)charter(dot)net> wrote:
> Hi. I'm using PostgreSQL 7.4.2 under Fedora Core 1.
> I have two tables with a single varchar(32) column in each. I'm trying
> to find all the rows from one table that don't exist in the other
> table. The query that I am using is:
> select u.user_name from users u where u.user_name not in (select
> user_name from iasusers);
> (Actually, I'm doing something a bit more complex but this illustrates
> the problem.)
> It always seems to return 0 rows. As a test, I inserted a row into
> users that I knew wasn't in iasuses but it didn't make a difference.
> If I remove the 'not', the query returns the rows that exist in both
> If I replace the subselect with a list, it seems to work the way that
> I'd expect, i.e. "not in ('vic', 'joe')" it shows all the rows from
> users except for vic and joe.
> Am I doing something wrong or is this a bug?
Are there any nulls in iasusers.user_name?
In response to
pgsql-bugs by date
|Next:||From: Vic Ricker||Date: 2004-05-26 19:42:06|
|Subject: Re: Question regarding 'not in' and subselects|
|Previous:||From: Vic Ricker||Date: 2004-05-26 17:57:37|
|Subject: Question regarding 'not in' and subselects|