如何從兩個表中正確選擇（SQL）

Question

我的數據庫Sales和Appliances中有兩個表：

銷售

SaleDate   EmployeeID AppID Qty
---------- ---------- ----- -----------
2010-01-01 1412       150   1
2010-01-05 3231       110   1
2010-01-03 2920       110   2
2010-01-13 1412       100   1
2010-01-25 1235       150   2
2010-01-22 1235       100   2
2010-01-12 2920       150   3
2010-01-14 3231       100   1
2010-01-15 1235       300   1
2010-01-03 2920       200   2
2010-01-31 2920       310   1
2010-01-05 1412       420   1
2010-01-15 3231       400   2

家電

ID   AppType              StoreID Cost          Price
---- -------------------- ------- ------------- -------------
100  Refrigerator         22      150           250
110  Refrigerator         20      175           300
150  Television           27      225           340
200  Microwave Oven       22      120           180
300  Washer               27      200           325
310  Washer               22      280           400
400  Dryer                20      150           220
420  Dryer                22      240           360

我如何獲得此結果表。 （其中列出了冰箱的銷售數量和每次銷售，也顯示了總銷售價格（總銷售價格=數量*價格）。

AppID AppType          Qty         total sale price
----- ---------------- ----------- ----------------
110   Refrigerator     1           300
110   Refrigerator     2           600
100   Refrigerator     1           250
100   Refrigerator     2           500
100   Refrigerator     1           250

---

我的嘗試：

SELECT AppID, AppType, Qty, (Qty * Price) as 'total sale price'
FROM Sales s, Appliances a
WHERE (AppID) IN (SELECT ID FROM Appliances WHERE AppType = 'Refrigerator')
AND (AppType) IN ('Refrigerator')

目前生產

AppID AppType              Qty         total sale price
----- -------------------- ----------- ----------------
110   Refrigerator         1           250
110   Refrigerator         1           300
110   Refrigerator         2           500
110   Refrigerator         2           600
100   Refrigerator         1           250
100   Refrigerator         1           300
100   Refrigerator         2           500
100   Refrigerator         2           600
100   Refrigerator         1           250
100   Refrigerator         1           300

Answer 1

在sales.AppId = appliances.ID上join sales.AppId = appliances.ID

select s.AppId, a.AppType, s.Qty, 
   a.Price * s.Qty as total
from appliances a
join sales s on s.AppId = a.ID
where a.AppType = 'Refrigerator'

Answer 2

您可以使用JOIN執行此操作：

在線演示

SELECT
    AppID   = p.ID,
    p.AppType,
    s.Qty,
    [Total Sales Price] = s.Qty * p.Price
FROM Sales s
INNER JOIN Appliances p
    ON p.ID = s.AppID
WHERE p.AppType = 'Refrigerator'

注意

• 您需要避免使用舊式JOIN語法並改為使用JOIN關鍵字。