RE: anti-join with SQL::Statement?

[email protected] ("Ludwig, Michael")
Newsgroups perl.dbi.users
Message-ID <[email protected]>
> So the next thing I tried was the anti-join (see
> 
>   http://en.wikipedia.org/wiki/Relational_algebra#Antijoin

First time I hear of this "antijoin".

The example given on the Wiki page doesn't make much sense
to me. Isn't is simply an OUTER JOIN where you're looking
for NULL on the right-hand side?

SELECT E.Name, D.DeptName
FROM Employee AS E
LEFT JOIN Dept AS D ON E.DeptName = D.DeptName
WHERE D.DeptName IS NULL

-- 
Michael Ludwig
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.