compare data and results that don't match

We are importing data from two different sources into two tables. We want to
compare the data and have the results that don't match
in a third table or even a report that we can export to excel.

I assume that you want to list out the unmatching records based on primary key. If so the following will work.
Select * from tableA

SELECT TableA.*
FROM Address LEFT JOIN Address AS TableB ON TableA.Primarykeyfieldname = TableB.PrimarykeyfieldName
WHERE (((TableB.PrimarykeyName) Is Null));

will list all records in tableA not available in TableB.

visit this link also

http://www.rogersaccesslibrary.com/...reTwoTables.mdb