Re: Alias in the HAVING clause

On Tue, May 13, 2008 at 5:43 PM, Nathan Thatcher  wrote:
> Is this the correct way to do this, or is there a better way / a way
> to get PostgreSQL to recognize an alias in the HAVING clause?

As Tom pointed out, f1's not in scope for the HAVING clause. If you're
that concerned about expression duplication, you could move the
calculation into a sub-select:

SELECT COUNT(*), f1 FROM (SELECT id % 3 AS f1 FROM table) t1 GROUP BY
f1 HAVING f1 <> 0;

-- 
- David T. Wilson
david.t.wilson@gmail.com