First - Thank you to all that spent time working on a solution.

Lamprey13's solution is hitting on the correct records. If you look at the tmpOrders data sorted by recordid and orderdate, recordid 2 is a match for recordid 1 based on ProductID,OrderDate,ProductClass, and ProductType. Also, recordid 5 is a match for recordid 4 based on the same fields sorted by orderdate.

My next challenge is to include both the matched data (as the query is doing now) and the data from the recordid being evaluated.

Ex: If recordid 2 is found as a match to recordid 1, return the order details for both record id's. Is this possible?