I finally found a great solution. Here it is:
-- Update SequenceNumber - 1st step, copy generated number to 
SequenceNumber
UPDATE #outCOMMENTS
	SET SequenceNumber = GeneratedSeq

-- Update SequenceNumber - 2nd step, change SequenceNumber to start with 
1, 2 etc. for each PPOID
UPDATE #outCOMMENTS
	SET SequenceNumber = (SELECT COUNT(*) FROM #outCOMMENTS C2
	    WHERE #outCOMMENTS.PPOID = C2.PPOID AND  
                  #outCOMMENTS.SequenceNumber >= C2.SequenceNumber) 

> Hi. 
> 
> I have a very perplexing problem. I sent out a previous message 
regarding 
> changing a variable value between several unions. However, I don't think 
> that logic will work with what I'm trying to achieve.
> 
> The end result of a COMMENT table should look like this:
>     PPOID     SequenceNumber      Comment
>     -----     --------------      -------
>      ABC            1             This is comment1 for ABC
>      ABC            2             This is comment2 for ABC
>      ABC            3             This is comment3 for ABC
>      DEF            1             This is comment1 for DEF
>      GHI            1             This is comment1 for GHI
>      GHI            2             This is comment2 for GHI
> 
> To achieve this result, I have multiple INSERT INTO COMMENT statements.
> 
> My problem is the SequenceNumber column. This column always has to start 
> at "1" when the PPOID is different. 
> 
> I thought about creating a temp table with no SequenceNumbers and then 
> doing an UPDATE on the temp table to get the correct SequenceNumber.
> 
> Using an UPDATE statement, how could I change the SequenceNumbers, 
always 
> starting with "1" on a PPOID change?
> 
> TIA.
> 
> Rita