excel questions

[zohar]

Respected Sir
A B C D
SUP NM D.O.DATE D.O.NO. INV. DATE INVOICE NO
SHOULD NOT ACCEPT AAA 2-MAY-04 1212 3-MAY-04 121
AAA 2-MAY-04 1212 3-MAY-04 121
SHOULD ACCEPT AAA 2-MAY-04 1212 3-MAY-04 121
AAA 2-MAY-05 1212 3-MAY-05 121
HERE SAME NUMBER OF D.O. OR INVOICE OBTAINED ON SAME DATE SHOULD BE NOT ALLOWE
BUT SHOULD ALLOW SAME NUMBER OF D.O. OR INVOICE OBTAINED IN DIFFERENT "YEARS"(A
DIFFERENT BOKS MAY HAVE BEEN USED IN DIFFERENT FINANCIAL YEARS
FOR BOTH D.O.(DELIVERY NUMBER) AND INVOICE NUMBER DUPLICATES FOR SAM
SUP NM(SUPPLIER NAME) IN SAME YEAR SHOULD NOT BE ALLOWED.ALSO INVOIC
DATE >= D.O. DATE
ZOHA
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