SQL GROUP BY 查找最大日期

Question

我有一个表Item,Pricelist1,HisDate和另一个表有Pricelist2 。

在以下查询中，我用于查找pricelist1和pricelist2小于用户输入日期

(Select
    MAX(ZA.CDU_HisDate) 'HISDATE',
    ZA.CDU_Item,
    ZA.CDU_CPrice1,
    ZB.CDU_Price2
 from TDU_PriceHistory ZA
 INNER Join TDU_PriceListDetails ZB on 
     ZA.CDU_CArtigo=ZB.CDU_Item and ZA.CDU_PL=ZB.CDU_PriceList
 where ZA.CDU_HisDate <= @todate
     and ZA.CDU_PL ='PL03'
 group by 
     ZA.CDU_cartigo,
     ZA.CDU_CPrice1,
     ZB.CDU_Price2
)

如果我仅通过cartigo使用GROUP by ，那就完美了。 如果我使用GROUP BY Item,Price1,Price2那么它的所有可用日期和价格详细信息。

我只想找到最大日期和相关价目表

Answer 1

如果我对你的问题理解正确，答案可能是这样的。

WITH 
    MaxDateForItem AS ( --  The max hisdate of item for user input date
        SELECT ZA.CDU_Item, MAX(ZA.CDU_HisDate) Max_CDU_HisDate 
        FROM TDU_PriceHistory ZA 
        WHERE ZA.CDU_HisDate <= @todate
            AND ZA.CDU_PL = 'PL03'
    ),
    ItemPriceAtMaxDate AS (
        SELECT T1.CDU_Item, T1.CDU_CPrice1, T1.CDU_HisDate, T1.CDU_CArtigo, T1.CDU_PL
        FROM TDU_PriceHistory T1
        INNER JOIN MaxDateForItem T2 ON T1.CDU_Item = T2.CDU_Item AND T1.CDU_HisDate = T2.Max_CDU_HisDate
        WHERE T1.CDU_PL = 'PL03'
    )
SELECT TMP1.CDU_HisDate AS HISDATE, TMP1.CDU_Item, TMP1.CDU_Price1, ZB.CDU_Price2
FROM ItemPriceAtMaxDate TMP1
INNER JOIN TDU_PriceListDetails ZB ON TMP1.CDU_CArtigo = ZB.CDU_Item
    AND TMP1.CDU_PL = ZB.CDU_PriceList;