Select 组中的最新值

Question

我想将列 LastSalePrice 添加到下面的查询中：

SELECT 
    P.SKU, 
    C.TotalSales,
    MIN(C.MinPriceChannel) OVER(PARTITION BY P.SKU) AS MinPrice,
    MAX(C.MaxPriceChannel) OVER(PARTITION BY P.SKU) AS MaxPrice,
    P.ProductName, 
    C.SalesChannel,
    C.Sales, 
    C.MinPriceChannel, 
    C.MaxPriceChannel
    --C.LastSalePrice
FROM
(
    SELECT 
        P.ProductId
        ,SUM(COUNT(*)) OVER(PARTITION BY P.ProductId) AS TotalSales
        ,COUNT(*) AS Sales
        ,MIN(OI.UnitPrice) AS MinPriceChannel
        ,MAX(OI.UnitPrice) AS MaxPriceChannel
        ,O.SalesChannel
        --LAST_VALUE(OI.UnitPrice) OVER (PARTITION BY P.ProductId ORDER BY O.SalesDate) as LastSalePrice
    FROM Product P
    JOIN OrderItem OI ON OI.ProductId = P.ProductId
    JOIN Orders O ON O.OrderId = OI.OrderId
    WHERE 
        O.SalesDate >= DATEADD(YEAR, -1, GETDATE())
    GROUP BY 
        P.ProductId,
        O.SalesChannel
) C
JOIN Product P ON P.ProductId = C.ProductId
ORDER BY P.ProductName ASC, C.SalesChannel ASC

我对我尝试过的内容发表评论 - 使用 last_value 函数 - 但它说我不能按 O.SalesDate 排序，因为它不包含在聚合函数中。

如何select每个产品和每个销售渠道的最后销售价格？

预期输出：

SKU	TotalSales	MinPrice	MaxPrice	ProductName	SalesChannel	Sales	MinPriceChannel	MaxPriceChannel	LastSalePrice
0002	9	12.42	14.99	Canned Unicorn Meat	eGulf	3	12.42	13.99	13.99
0002	9	12.42	14.99	Canned Unicorn Meat	Kasim	3	12.72	14.95	12.72
0002	9	12.42	14.99	Canned Unicorn Meat	Nile	3	12.99	14.99	14.99
0001	9	43.99	50.00	Whosebug Keyboard	eGulf	3	46.60	49.75	46.60
0001	9	43.99	50.00	Whosebug Keyboard	Kasim	3	43.99	50.00	48.99
0001	9	43.99	50.00	Whosebug Keyboard	Nile	3	44.99	49.99	47.99

Table 定义和示例数据

CREATE TABLE Product 
(
    ProductId int NOT NULL PRIMARY KEY IDENTITY(1,1),
    ProductName varchar (255) NOT NULL,
    SKU varchar(30) NOT NULL
)
GO

CREATE TABLE Orders 
(
    OrderId int NOT NULL PRIMARY KEY IDENTITY(1, 1),
    SalesDate datetime2 NOT NULL default(GETDATE()),
    SalesChannel varchar(30) NOT NULL
)
GO

CREATE TABLE OrderItem 
(
    OrderItemId int NOT NULL PRIMARY KEY IDENTITY(1, 1),
    ProductId int FOREIGN KEY REFERENCES Product(ProductId),
    OrderId int FOREIGN KEY REFERENCES Orders(OrderId),
    UnitPrice decimal(12, 2) NOT NULL
)

GO
INSERT INTO Product (ProductName, SKU) 
VALUES ('Whosebug Keyboard', '0001'), 
       ('Canned Unicorn Meat', '0002');
GO

INSERT INTO Orders (SalesDate, SalesChannel) 
VALUES ('2021-04-08', 'Nile'), ('2021-04-09', 'Nile'), ('2021-04-10',  'Nile'),
       ('2021-04-11', 'Nile'), ('2021-04-12', 'Nile'), ('2021-04-13', 'Nile'),
       ('2021-04-08', 'Kasim'), ('2021-04-09', 'Kasim'), ('2021-04-10', 'Kasim'),
       ('2021-04-11', 'Kasim'), ('2021-04-12', 'Kasim'), ('2021-04-13', 'Kasim'),
       ('2021-04-08', 'eGulf'), ('2021-04-09', 'eGulf'), ('2021-04-10', 'eGulf'),
       ('2021-04-11', 'eGulf'), ('2021-04-12', 'eGulf'), ('2021-04-13', 'eGulf');
GO

INSERT INTO OrderItem (ProductId, OrderId, UnitPrice) 
VALUES (1, 1, 49.99), (1, 2, 44.99), (1, 3, 47.99),
       (2, 4, 12.99), (2, 5, 13.99), (2, 6, 14.99),
       (1, 7, 43.99), (1, 8, 50.00), (1, 9, 48.99),
       (2, 10, 14.95), (2, 11, 13.50), (2, 12, 12.72),
       (1, 13, 47.89), (1, 14, 49.75), (1, 15, 46.60),
       (2, 16, 12.42), (2, 17, 13.59), (2, 18, 13.99);
GO

Answer 1

您可以使用标量子查询

WITH src AS(
    SELECT OI.*, O.SalesDate, O.SalesChannel
    FROM OrderItem OI 
    JOIN Orders O ON O.OrderId = OI.OrderId
    WHERE 
        O.SalesDate >= DATEADD(YEAR, -1, GETDATE())
)
SELECT 
    P.SKU, 
    C.TotalSales,
    MIN(C.MinPriceChannel) OVER(PARTITION BY P.SKU) AS MinPrice,
    MAX(C.MaxPriceChannel) OVER(PARTITION BY P.SKU) AS MaxPrice,
    P.ProductName, 
    C.SalesChannel,
    C.Sales, 
    C.MinPriceChannel, 
    C.MaxPriceChannel,
    C.LastSalePrice
FROM
(
    SELECT 
        P.ProductId
        ,SUM(COUNT(*)) OVER(PARTITION BY P.ProductId) AS TotalSales
        ,COUNT(*) AS Sales
        ,MIN(OOI.UnitPrice) AS MinPriceChannel
        ,MAX(OOI.UnitPrice) AS MaxPriceChannel
        ,OOI.SalesChannel
        ,(SELECT TOP 1 z.UnitPrice
           FROM src z 
           WHERE P.ProductId = z.ProductId AND OOI.SalesChannel = z.SalesChannel
           ORDER BY z.SalesDate DESC) as LastSalePrice
    FROM Product P
    JOIN src OOI ON OOI.ProductId = P.ProductId
    GROUP BY 
        P.ProductId,
        OOI.SalesChannel
) C
JOIN Product P ON P.ProductId = C.ProductId
ORDER BY P.ProductName ASC, C.SalesChannel ASC

Answer 2

我不得不使用 FIRST_VALUE，LAST VALUE 对我不起作用。

;WITH T1 AS (
    SELECT 
        OI.ProductId
        ,OI.UnitPrice
        ,O.SalesChannel
        ,O.SalesDate
        ,FIRST_VALUE(UnitPrice) OVER (PARTITION BY OI.ProductId, SalesChannel ORDER BY O.SalesDate DESC) as LastSalePrice
    FROM OrderItem OI
    JOIN Orders O ON O.OrderId = OI.OrderId
    WHERE 
        O.SalesDate >= DATEADD(YEAR, -1, GETDATE())
)
SELECT 
    P.SKU, 
    C.TotalSales,
    MIN(C.MinPriceChannel) OVER(PARTITION BY P.SKU) AS MinPrice,
    MAX(C.MaxPriceChannel) OVER(PARTITION BY P.SKU) AS MaxPrice,
    P.ProductName, 
    C.SalesChannel,
    C.Sales, 
    C.MinPriceChannel, 
    C.MaxPriceChannel,
    C.LastSalePrice
FROM
(
    SELECT 
        ProductId
        ,SUM(COUNT(*)) OVER(PARTITION BY ProductId) AS TotalSales
        ,COUNT(*) AS Sales
        ,MIN(UnitPrice) AS MinPriceChannel
        ,MAX(UnitPrice) AS MaxPriceChannel
        ,SalesChannel
        ,MAX(LastSalePrice) AS LastSalePrice
    FROM T1
    GROUP BY 
        ProductId,
        SalesChannel
) C
JOIN Product P ON P.ProductId = C.ProductId
ORDER BY P.ProductName ASC, C.SalesChannel ASC

Select 组中的最新值

Select most recent value in a group

sql

sql-server

group-by

greatest-n-per-group

sql-server-2019