Re: Alias in the HAVING clause - Mailing list pgsql-general

From David Wilson
Subject Re: Alias in the HAVING clause
Date
Msg-id e7f9235d0805131601x25817293o75bcfde136d9b569@mail.gmail.com
Whole thread Raw
In response to Alias in the HAVING clause  ("Nathan Thatcher" <n8thatcher@gmail.com>)
Responses Re: Alias in the HAVING clause
List pgsql-general
On Tue, May 13, 2008 at 5:43 PM, Nathan Thatcher <n8thatcher@gmail.com> 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

pgsql-general by date:

Previous
From: Tom Lane
Date:
Subject: Re: Alias in the HAVING clause
Next
From: Reece Hart
Date:
Subject: Re: Unloading a table consistently