SQL Server : MAX (DATE)가있는 행만 선택

SQL Server : MAX (DATE)가있는 행만 선택

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데이터 테이블이 있습니다 (db는 MSSQL입니다).

    ID  OrderNO PartCode  Quantity DateEntered
    417 2144     44917    100      18-08-11
    418 7235     11762    5        18-08-11
    419 9999     60657    100      18-08-11
    420 9999     60657    90       19-08-11

OrderNO, PartCode 및 Quantity를 반환하는 쿼리를 만들고 싶지만 마지막으로 등록 된 주문에 대해서만.

예제 테이블에서 다음 정보를 얻고 싶습니다.

     OrderNO PartCode  Quantity     
     2144     44917    100      
     7235     11762    5        
     9999     60657    90      

주문 9999에 대해 하나의 라인 만 반품되었습니다.

감사!

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가능하다면 rownumber() over(...)....

select OrderNO,
       PartCode,
       Quantity
from (select OrderNO,
             PartCode,
             Quantity,
             row_number() over(partition by OrderNO order by DateEntered desc) as rn
      from YourTable) as T
where rn = 1      

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ROW_NUMBER()가능한 경우 가장 좋은 방법은 Mikael Eriksson 입니다.

차선책은 Cularis의 답변에 따라 쿼리에 참여하는 것입니다.

또는 가장 간단하고 직접적인 방법은 WHERE 절의 상관 하위 쿼리입니다.

SELECT
  *
FROM
  yourTable AS [data]
WHERE
  DateEntered = (SELECT MAX(DateEntered) FROM yourTable WHERE orderNo = [data].orderNo)

또는...

WHERE
  ID = (SELECT TOP 1 ID FROM yourTable WHERE orderNo = [data].orderNo ORDER BY DateEntered DESC)

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select OrderNo,PartCode,Quantity
from dbo.Test t1
WHERE EXISTS(SELECT 1
         FROM dbo.Test t2
         WHERE t2.OrderNo = t1.OrderNo
           AND t2.PartCode = t1.PartCode
         GROUP BY t2.OrderNo,
                  t2.PartCode
         HAVING t1.DateEntered = MAX(t2.DateEntered))

이것은 위에 제공된 모든 쿼리 중 가장 빠릅니다. 쿼리 비용은 0.0070668입니다.

Mikael Eriksson이 작성한 위의 기본 답변은 쿼리 비용이 0.0146625입니다.

You may not care about the performance for such a small sample, but in large queries, it all adds up.

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SELECT t1.OrderNo, t1.PartCode, t1.Quantity
FROM table AS t1
INNER JOIN (SELECT OrderNo, MAX(DateEntered) AS MaxDate
            FROM table
            GROUP BY OrderNo) AS t2
ON (t1.OrderNo = t2.OrderNo AND t1.DateEntered = t2.MaxDate)

The inner query selects all OrderNo with their maximum date. To get the other columns of the table, you can join them on OrderNo and the MaxDate.

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If you have indexed ID and OrderNo You can use IN: (I hate trading simplicity for obscurity, just to save some cycles):

select * from myTab where ID in(select max(ID) from myTab group by OrderNo);

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For MySql you can do something like the following:

select OrderNO, PartCode, Quantity from table a
join (select ID, MAX(DateEntered) from table group by OrderNO) b on a.ID = b.ID

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And u can also use that select statement as left join query... Example :

... left join (select OrderNO,
   PartCode,
   Quantity from (select OrderNO,
         PartCode,
         Quantity,
         row_number() over(partition by OrderNO order by DateEntered desc) as rn
  from YourTable) as T where rn = 1 ) RESULT on ....

Hope this help someone that search for this :)

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rownumber() over(...) is working but I didn't like this solution for 2 reasons. - This function is not available when you using older version of SQL like SQL2000 - Dependency on function and is not really readable.

Another solution is:

SELECT tmpall.[OrderNO] ,
       tmpall.[PartCode] ,
       tmpall.[Quantity] ,
FROM   (SELECT [OrderNO],
               [PartCode],
               [Quantity],
               [DateEntered]
        FROM   you_table) AS tmpall
       INNER JOIN (SELECT [OrderNO],
                          Max([DateEntered]) AS _max_date
                   FROM   your_table
                   GROUP  BY OrderNO ) AS tmplast
               ON tmpall.[OrderNO] = tmplast.[OrderNO]
                  AND tmpall.[DateEntered] = tmplast._max_date

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Try to avoid IN use JOIN

SELECT SQL_CALC_FOUND_ROWS *  FROM (SELECT  msisdn, callid, Change_color, play_file_name, date_played FROM insert_log
   WHERE play_file_name NOT IN('Prompt1','Conclusion_Prompt_1','silent')
 ORDER BY callid ASC) t1 JOIN (SELECT MAX(date_played) AS date_played FROM insert_log GROUP BY callid) t2 ON t1.date_played=t2.date_played

참고URL : https://stackoverflow.com/questions/7118170/sql-server-select-only-the-rows-with-maxdate