Hello
I have two Tables.
tblMain(MainID)
tblSec(FamID, Group, MainID)
MainID has same attribute in both tables
tblMain has the correct records.

How can I delete all records from tblSec not present in tblMain? Could you
tell me the kind of query. I'm studying Relational Algebra by myself and this
example would help me to learn
Thanks in advance