Sql server 具有联接的每个组的最大N：获取错误的最大/最小值

可悲的是，流行的“每个组最大N个”查询的另一个变体，但它一直在踢我的屁股，我真的需要一些澄清（问题尽可能简化）：

我有两张桌子：

Items
-----
ItemID 
ProductName


Inventory
---------
InventoryID
ItemID
Condition
Price

我正试图构造一个查询，它显示给定条件下每个项目的InventoryID、ItemID、ItemName、Condition和Max price

i、 e.给定

Inventory
---------
InventoryID  ItemID  Condition   Price
INV123       ITEM001 NEW         $3.99
INV001       ITEM001 NEW         $3.79
INV031       ITEM001 USED        $1.23
INV234       ITEM001 USED        $1.99

及项目：

ItemID    ItemName
ITEM001   Lg Widget
ITEM002   Sm Widget

我希望：

ItemID  ItemName  Condition  MaxPrice MaxPriceInventoryID  
ITEM001 Lg Widget NEW        $3.99    INV123
ITEM001 Lg Widget USED       $1.99    INV234  

我正在尝试这个：

SELECT 
  ItemID, ItemName, b.condition, b.maxprice, 
    InventoryID as MaxPriceInventoryID
FROM
  Items I join inventory v On i.ItemID= v.ItemID
    join (
        select inventory.ItemID, max(Price) as MaxPrice, condition
            from inventory join Items on inventory.ItemID = Items.ItemID
            group by inventory.ItemID, condition) as b 
    on b.ItemID = v.ItemID and b.MaxPrice = v.Price
 ORDER BY
    ItemName, Condition

不幸的是，这并没有给出期望的结果：它似乎在所有条件下偶尔返回商品的最高价格，而不是在给定条件下返回商品的最高价格

---

想法？

我并不完全清楚您的数据是如何关联的，或者您需要如何过滤

我要么这样做：

SELECT ii.ItemID
    ,ii.ItemName
    ,ii.Condition
    ,ii.Price AS MaxPrice
    ,ii.MaxPriceInventoryID
FROM (
    SELECT i.ItemID
        ,i.ItemName
        ,i.ProductName
        ,v.InventoryID
        ,v.Condition
        ,v.Price
        ,DENSE_RANK() OVER (PARTITION BY v.ItemID, v.Condition ORDER BY v.Price DESC) AS R
    FROM Items i
    INNER JOIN Inventory v
        ON  i.ItemID = v.ItemID
    WHERE 1 = 1 /* Place your filtering conditionals here */
    ) AS ii
WHERE ii.R = 1
ORDER BY ii.ItemName
    ,ii.Condition

SELECT i.ItemID
    ,i.ItemName
    ,vv.Condition
    ,vv.Price AS MaxPrice
    ,vv.MaxPriceInventoryID
FROM Items i
INNER JOIN (
    SELECT v.ItemID
        ,v.InventoryID
        ,v.Condition
        ,v.Price
        ,DENSE_RANK() OVER (PARTITION BY v.ItemID, v.Condition ORDER BY v.Price DESC) AS R
    FROM  Inventory v
    WHERE 1 = 1 /* Place your filtering conditionals here */
    ) AS vv
    ON  i.ItemID = vv.ItemID
WHERE vv.R = 1
ORDER BY i.ItemName
    ,vv.Condition

或者这样：

SELECT ii.ItemID
    ,ii.ItemName
    ,ii.Condition
    ,ii.Price AS MaxPrice
    ,ii.MaxPriceInventoryID
FROM (
    SELECT i.ItemID
        ,i.ItemName
        ,i.ProductName
        ,v.InventoryID
        ,v.Condition
        ,v.Price
        ,DENSE_RANK() OVER (PARTITION BY v.ItemID, v.Condition ORDER BY v.Price DESC) AS R
    FROM Items i
    INNER JOIN Inventory v
        ON  i.ItemID = v.ItemID
    WHERE 1 = 1 /* Place your filtering conditionals here */
    ) AS ii
WHERE ii.R = 1
ORDER BY ii.ItemName
    ,ii.Condition

SELECT i.ItemID
    ,i.ItemName
    ,vv.Condition
    ,vv.Price AS MaxPrice
    ,vv.MaxPriceInventoryID
FROM Items i
INNER JOIN (
    SELECT v.ItemID
        ,v.InventoryID
        ,v.Condition
        ,v.Price
        ,DENSE_RANK() OVER (PARTITION BY v.ItemID, v.Condition ORDER BY v.Price DESC) AS R
    FROM  Inventory v
    WHERE 1 = 1 /* Place your filtering conditionals here */
    ) AS vv
    ON  i.ItemID = vv.ItemID
WHERE vv.R = 1
ORDER BY i.ItemName
    ,vv.Condition

如果即使在价格上有联系的情况下，您也只需要一个ItemID，那么您可以用

行号（）替换
密集列号（）
。但是，除非在
OVER（）
子句中的
orderby
中添加一个键字段，否则结果将不具有确定性