here is the SQL statement straight out of Access (using the Biblio.mdb that ships with VB)
Code:
SELECT Publishers.Zip, Count(Publishers.Zip) AS CountOfZip
FROM Publishers
GROUP BY Publishers.Zip;
You can right click in the Query creation table and select Totals change the one you want to count to 'count' and the rest to 'group by' if you want to show the zip and the count then make to spots for zip one with count one with group by.
KEY info if other info is in the query (like Customer name) that shares the zip but not the other info it will NOT be counted as the same zip.
That should give you some direction.