actually i've been hearing about that of rushmore technology but i really can't find any good article to read on.

anyway, do you know any way how can i get records from table A that does not exist in table B?

i use this SQL:

SELECT * FROM xm a WHERE NOT EXISTS (SELECT checkno FROM xa b WHERE a.checkno=b.checkno .AND. a.brcode=b.brcode .AND. a.agycode=b.agycode)

any help?