[vox-tech] SQL help - unions

[Peter Jay Salzman]

On Wed 21 Jul 04,  1:36 AM, David Hummel <dhml at comcast.net> said:
> On Wed, Jul 21, 2004 at 12:00:39AM -0700, Jeff Newmiller wrote:
> > 
> > A headcount is not the same as a roster... neither Peter's nor
> > Michael's version was counting anything.
> 
> I assumed what Peter was after was a list of unique SSN's for "race = 0"
> students in Fall_2003 and Spring_2004.
 
Unfortunately, I'm being forced to use MS Access at work.  In Access, a
roster always gives you a headcount (but a headcount doesn't necessarily
give you a roster).  So a roster is good too.

Actually, Access is kind of neat, but it has a major drawback.  You can
build fairly complex queries with a graphical interface.  You can also
build them using SQL.  But the GUI is very convenient.  Until you hit
something the GUI can't do, like this.

I've been told the GUI query builder can't accomplish this task because
the database is designed poorly, as Jeff pointed out.  But these are
actually text files written by a mainframe that are sent to the state to
report various things about our college.  They weren't meant to be part
of a database.  That was my idea.  :)

The downside of using Access (other than the obvious) is that you tend
to rely on the GUI interface when you should be concentrating on your
basic SQL skills to prepare yourself for the inevitable time when you
HAVE to use SQL because the GUI can't do it (like now - there's no GUI
for unions).

Pete

-- 
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