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And Now?
•I still have only the result of SeattleView:
•         SELECT  buyer, seller, product, store
•         FROM     Person, Purchase, Product
•         WHERE   Person.city = ‘Seattle’    AND
•                          Person.per-name = Purchase.buyer AND
•                          Purchase.product = Product.name
•but I want to answer the query
•         SELECT  buyer, seller
•         FROM     Person, Purchase
•         WHERE   Person.city = ‘Seattle’    AND
•                          Person.per-name = Purchase.buyer.
•