>>>So, by removing duplicates, I am removing any "H"
>>> records that match a "C" record. All the
>>> remaining "H" records I know must exist only
>>> in the history table.
>
>>I see.
>
>Do you? Or are you just saying that so I'll stop explaining? < BG >
Well...to be honest...

Just kidding, after I re-read your postings and the proposed solution, I think I understood why.