Question

我想要db中每个EntityCode的最高BID和最低ASK（价格）的表。

以下两组代码返回两个结果集但我还无法找到/弄清楚如何加入它们：

获得最高出价

(SELECT *   FROM    
   (SELECT 
        Contracts.Orders2Buy.EntityCode,
        Contracts.Orders2Buy.Bid,       
        Contracts.Orders2Buy.NumContractsStillAvailable,
        Contracts.Orders2Buy.TimePlaced,
        RANK() OVER (PARTITION BY EntityCode  
               ORDER BY Contracts.Orders2Buy.Bid DESC, 
               Contracts.Orders2Buy.TimePlaced DESC) AS Rank
    FROM
        Contracts.Orders2Buy
    WHERE
        Contracts.Orders2Buy.NumContractsStillAvailable > 0) AS temp
WHERE temp.Rank = 1)

获得最低要求

(SELECT *   FROM    
(   SELECT 
        Contracts.Orders2Sell.EntityCode,
        Contracts.Orders2Sell.Ask,          
        Contracts.Orders2Sell.NumContractsStillAvailable AS AskVolume,
        Contracts.Orders2Sell.TimePlaced,
        RANK () OVER (  PARTITION BY EntityCode     
                ORDER BY    Contracts.Orders2Sell.Ask ASC, 
                Contracts.Orders2Sell.TimePlaced DESC) AS Rank
    FROM
        Contracts.Orders2Sell
    WHERE
        Contracts.Orders2Sell.NumContractsStillAvailable > 0) AS temp2
WHERE temp2.Rank = 1)

Answer 1

使用JOIN将三个结果集合并为一个结果，而不是UNION。

SELECT  *
FROM    highestBid hb
        JOIN lowestAsk la ON hb.stock_symbol = la.stock_symbol
        JOIN mostRecent mr ON la.stock_symbol = mr.stock_symbol

将每个集合中所需的字段替换为*

Answer 2

我想要完成的任务需要加入上面的代码块，如下所示：

SELECT * FROM 

      (Code block 1) t1

INNER JOIN

      (Code block 2) t2

ON t1.EntityCode = t2.EntityCode

SQL Server使用Rank和Partition加入查询

2 个答案: