There seems to be a mistake on the table

Listing 5.4: The "Activity totals by date" query

Because option 2 seems more efficient on IO as it sends this results.

CREATE NONCLUSTERED INDEX FK_ProductID_ModifiedDate

ON SalesOrderDetail_index (ProductID, ModifiedDate)

SELECT ModifiedDate ,

ProductID ,

SUM(OrderQty) 'No of Items' ,

AVG(UnitPrice) 'Avg Price' ,

SUM(LineTotal) 'Total Value'

FROM SalesOrderDetail_index

WHERE ModifiedDate = '2003-10-01'

GROUP BY ModifiedDate ,

ProductID ;

Tabla 'SalesOrderDetail_index'. Recuento de exámenes 1, lecturas lógicas 384

Tiempo de CPU = 0 ms, tiempo transcurrido = 7 ms.