> On Mon, Jul 25, 2005 at 06:11:08PM -0300, Marc G. Fournier wrote:
> >
> > Just curious as to whether or not a warning or something should be
issued
> > in a case like:
> >
> > SELECT c.*
> > FROM company c, company_summary cs
> > WHERE c.id = cs.id
> > AND cs.detail = 'test'
> > ORDER BY cs.fullname;
> >
> > Unless I'm missing something, the ORDER BY clause has no effect, but an
> > EXPLAIN shows it does take extra time, obviously ...
>
> Uh, I'd hope it had an effect. Note that RDBMSes have been moving
> towards allowing fields in ORDER BY that aren't in the SELECT list,
> though in the past it was common that anything in ORDER BY had to also
> be in SELECT.
Prior to SQL:1999, the spec required that any column referenced in an ORDER
BY clause must also be referenced in the SELECT.
SQL:1999 (feature E1210-02) relaxed this to allow columns to be specified in
the ORDER BY clause but not in the SELECT.
--
Matt Emmerton
