Okay, you should take a look at the links in my signature line as posting a more complete question helps you get better answers.
When you say you get multiple rows for some does that mean that you are getting the same data except for the date? Something like this:
FirstName LastName ChangeDate
--------- --------- ------------
Jack Corbett 01/27/1998
Jack Corbett 07/01/2008
Steve Jones 06/25/2007
Or are there other differences in the data as well?
If you post some schemas and some sample data it would be a lot easier to answer your question.
Jack Corbett
Consultant - Straight Path Solutions
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