Thank you very much for your suggestion. I was able to use Merge to get the result that I wanted, but I am having issues making my code into a stored procedure. Below is my code:

MERGE AccountMaster2 AS TARGET

USING RevJuly2010$ AS SOURCE

ON (TARGET.AccountID = SOURCE.AccountID)

WHEN MATCHED THEN

UPDATE SET

target.AccountNumber = Source.AccountNumber,

WHEN NOT MATCHED BY TARGET THEN

INSERT (AccountID,AccountNumber)

VALUES (SOURCE.AccountID, Source.AccountNumber)

OUTPUT $action,

DELETED.AccountID AS TargetAccountID,

INSERTED.AccountID AS SourceAccountID,

deleted.AccountNumber as TargetAccountNumber,

inserted.AccountNumber as SourceAccountNumber,

;

Would I be able to make a stored procedure so that I only need to input the only TABLE NAME such as "RevJuly2010$" every month (I don't need to change the columns that I need to merge)?