Unique identifier

[Chris]

Can someone tell me how I could attach a unique indentifier to an order
number. I would like the identifer to increment until the order number
changes sort of like the following:

Order num Identifier

75621 1
75621 2
75621 3
75622 1
75623 1
75623 2

Thanks for any sugestions.
Chris

 

[KARL DEWEY]

That would be ranking in a group.
SELECT Q.Group, Q.Points, (SELECT COUNT(*) FROM Product Q1
WHERE Q1.[Group] = Q.[Group]
AND Q1.Points < Q.Points)+1 AS Rank
FROM Product AS Q
ORDER BY Q.Group, Q.Points;