[vox-tech] SQL help - unions

[Peter Jay Salzman]

Total newbie here.  I know less about SQL than I do about xkb.   ;-)

I have two tables, with the same structure.  Call them [Fall 2003] and
[Spring 2004].  They each hold data about enrolled students.  One of the
fields of these tables is SSN (social security number).

I can get an unduplicated headcount for the academic year with:

   SELECT SSN from [Fall 2003]
   UNION
   SELECT SSN from [Spring 2004];

There's also a field called "race".  If the race field is 0, the student
is African American.

How would I modify the above SQL statement to list the unduplicated
headcount of all African Americans?  I would like to do something like:

   SELECT SSN from [Fall 2003]
   UNION
   SELECT SSN from [Spring 2004]
   and race == 1;

but of course that doesn't work.  :)

Thanks!
Pete