Question

我需要在1996年9月计算出每种产品占总收入的比例。数据在3个表中

表1：订单详细信息

OrderDetailID   OrderID ProductID   Quantity-
-------------------------------------------
1               10248       11      12
2               10248       42      10
3               10248       72       5
4               10249       14       9
5               10249       51      40
6               10250       41      10

表＃2：产品

ProductID   ProductName                     SupplierID  CategoryID       Unit           Price
-----------------------------------------------------------------------------------------------------
    1       Chais                               1           1       10  boxes x 20 bags 18
    2       Chang                               1           1       24 - 12 oz bottles  19
    3       Aniseed Syrup                       1           2       12 - 550 ml bottles 10
    4       Chef Anton's Cajun Seasoning        2           2       48 - 6 oz jars      22
    5       Chef Anton's Gumbo Mix              2           2       36 boxes            21.35
    6       Grandma's Boysenberry Spread        3           2       12 - 8 oz jars      25
    7       Uncle Bob's Organic Dried Pears     3           7       12 - 1 lb pkgs.     30

表＃3：订单

OrderID CustomerID  EmployeeID  OrderDate   ShipperID
------------------------------------------------------
10248   90          5           1996-07-04  3
10249   81          6           1996-07-05  1
10250   34          4           1996-07-08  2
10251   84          3           1996-07-08  1
10252   76          4           1996-07-09  2
10253   34          3           1996-07-10  2
10254   14          5           1996-07-11  2

我猜这些步骤是：

内部将OrderDetails与Order by OrderID一起加入，以仅显示1996年9月的订单
内部将“第1步”的结果与“ Products by ProductID”相结合，并计算每种产品的收入占总收入的百分比

我已经完成了第一步

SELECT
    Orders.OrderID,
    Orders.OrderDate,
    OrderDetails.Quantity,
    OrderDetails.ProductID
FROM
    Orders
INNER JOIN
    OrderDetails ON  Orders.OrderID = OrderDetails.OrderID
WHERE
    OrderDate LIKE '1996-09%';

预期结果：

OrderID OrderDate   Quantity    ProductID
-----------------------------------------
10295   1996-09-02   4          56
10296   1996-09-03  12          11
10296   1996-09-03  30          16
10296   1996-09-03  15          69
10297   1996-09-04  60          39

但是我不知道如何执行步骤2。非常感谢你！

Answer 1

使用窗口功能：

SELECT od.ProductID,
       SUM(od.Quantity),
       SUM(od.Quantity) * 1.0 / SUM(SUM(od.Quantity)) OVER () as ratio
FROM Orders o INNER JOIN
     OrderDetails od
     ON o.OrderID = od.OrderID
WHERE o.OrderDate >= '1996-09-01' AND o.OrderDate < '1996-10-01'
GROUP BY od.ProductID;

Answer 2

W3Cschool的交互式SQL惯例似乎不支持窗口功能。而且，我没有找到定义变量的方法，因此不得不两次提到相同的常数（年和月）。在现实生活中，我建议使用解析函数，或者至少为多个地方使用的值声明一个变量。

无论如何，看起来像下面的代码可以满足您的需求：

SELECT 
  od.ProductID, 
  MIN(o.OrderDate) as SalesStart, 
  MAX(o.OrderDate) as SalesEnd, 
  SUM(od.Quantity) as SoldQty, 
  SUM(od.Quantity * p.Price) as SoldAmt, 
  SUM(od.Quantity * p.Price) * 1.0 / 
  (
    SELECT SUM(odAll.Quantity * pAll.Price) 
    FROM OrderDetails odAll 
    INNER JOIN Orders as oAll 
      ON oAll.OrderID = odAll.OrderID
    INNER JOIN Products as pAll
      ON odAll.ProductID =  pAll.ProductID
    WHERE oAll.OrderDate LIKE '1996-09%') as PortionInTotalSales
FROM Orders as o
INNER JOIN OrderDetails as od
  ON o.OrderID = od.OrderID
INNER JOIN Products as p
  ON od.ProductID =  p.ProductID  
WHERE o.OrderDate LIKE '1996-09%'
GROUP BY od.ProductID

内部联接多个SQL表并进行计算

2 个答案: