可搭配GROUPING使用，區分是否為匯總資料行。
DECLARE @TABLE TABLE (Pname VARCHAR(10),
SW VARCHAR(10),
Qty SMALLINT)
INSERT INTO @TABLE VALUES ('AA','1',50)
INSERT INTO @TABLE VALUES ('AA','2',70)
INSERT INTO @TABLE VALUES ('AA','2',35)
INSERT INTO @TABLE VALUES ('AA','3',36)
INSERT INTO @TABLE VALUES ('BB','1',25)
INSERT INTO @TABLE VALUES ('BB','2',10)
INSERT INTO @TABLE VALUES ('BB','2',20)
SELECT Pname,SW,Qty=SUM(Qty),GP=GROUPING(Pname)
FROM @TABLE
GROUP BY Pname,SW WITH ROLLUP
--查詢結果 Pname SW Qty GP ---------- ---------- ----------- ---- AA 1 50 0 AA 2 105 0 AA 3 36 0 AA NULL 191 0 BB 1 25 0 BB 2 30 0 BB NULL 55 0 NULL NULL 246 1參考自：MSDN-GROUPING (Transact-SQL)
