Editar: Se livrou ou o
MAX() OVER (PARTITION BY ...) como isso parecia matar o desempenho. ;WITH cte AS (
SELECT CustID ,
OrderDate,
DATEPART(YEAR, OrderDate)*12 + DATEPART(MONTH, OrderDate) AS YM
FROM Orders
),
cte1 AS (
SELECT CustID ,
OrderDate,
YM,
YM - DENSE_RANK() OVER (PARTITION BY CustID ORDER BY YM) AS G
FROM cte
),
cte2 As
(
SELECT CustID ,
MIN(OrderDate) AS Mn,
MAX(OrderDate) AS Mx
FROM cte1
GROUP BY CustID, G
HAVING MAX(YM)-MIN(YM) >=2
)
SELECT c.CustName, o.OrderDate, YEAR(o.OrderDate) AS YEAR
FROM Customers AS c INNER JOIN
Orders AS o ON c.CustID = o.CustID
INNER JOIN cte2 c2 ON c2.CustID = o.CustID and o.OrderDate between Mn and Mx
order by c.CustName, o.OrderDate
