新しい列のテーブル内の選択

Question

テーブルpricedata（添付ファイル参照）があります。私はこのテーブル（MinPrice of CompetitorとCompetitorID of MinPrice）に2つの余分な列を追加したいと思います。私は、列MinPrice of Competitorを取得するコードを書いたが、私はどのように2番目の列、任意の助けを得るために考えていないか？

コード：

select a.ValuationDate, a.shop, a.Itemcode, a.OwnPrice, 
     a.[sales price competitor], a.[competitor ID], b.MinPrice 
from [PriceTable] a 
    inner join 
     (select ValuationDate, Shop, ItemCode, 
       min([sales price competitor]) as MinPrice 
     FROM [PriceTable] 
     group by ValuationDate, Shop, ItemCode) b 
    on a.ValuationDate = b.ValuationDate 
    and a.Shop = b.Shop 
    and a.ItemCode = b.ItemCode 

実際のテーブル：

必要なテーブル：ここに行く

Answer 1

。お役に立てれば。

select 
    a.ValuationDate, 
    a.shop 
    a.Itemcode, 
    a.OwnPrice, 
    a.[sales price competitor], 
    a.[competitor ID], 
    b.MinPrice , 
    MINCOMPID.[competitor ID] AS 'CompetitorID of MinPrice' 
from [PriceTable] a 
inner join 
(
select ValuationDate, Shop, ItemCode, min([sales price competitor]) as MinPrice FROM [PriceTable] 
group by ValuationDate, Shop, ItemCode 
) b 
on a.ValuationDate=b.ValuationDate and a.Shop=b.Shop and a.ItemCode=b.ItemCode 
INNER JOIN [PriceTable] AS MINCOMPID 
ON MINCOMPID.ValuationDate=b.ValuationDate and MINCOMPID.Shop=b.Shop and MINCOMPID.ItemCode=b.ItemCode AND MINCOMPID.[sales price competitor]=b.MinPrice 

Answer 2

見てください（テストされていません）。最小/最大値はSELECT TOPであるとの行を取得する一般的な方法は、（1）.. DESC/ASC BY ORDER

select a.ValuationDate, a.shop, a.Itemcode, a.OwnPrice, 
     a.[sales price competitor], a.[competitor ID], 
     c.MinPrice, c.[competitor ID] 
from [PriceTable] a 
cross apply 
    (SELECT TOP(1) b.[competitor ID] 
       b.[sales price competitor] as MinPrice 
    FROM [PriceTable] b  
    WHERE a.ValuationDate = b.ValuationDate 
    and a.Shop = b.Shop 
    and a.ItemCode = b.ItemCode 
    ORDER BY b.[sales price competitor] DESC) c