按 2 个 ID 字段返回最新记录组

Question

I need to display the current status of a part ('approved' or 'not approved') I am setting up the status table as MaterialNo, ToolID, Status, Asofdate

the idea is I may have several tools approved and several not approved. I want to be able to see the most recent status for each tool but I don't want to see the historical status.

have tried to use MAX(Asofdate) and group by MaterialNo, ToolID, and Status but it returns all of the status history for each.

SELECT MaterialNo, ToolID, PPAPStatus, MAX(Asof) as "AsOf"
  FROM [MfgDataCollector].[dbo].[PPAPStatus]
  Group By MaterialNo, ToolID, PPAPStatus

The Status Table has this data:

MaterialNo  ToolID  Status          Asofdate
52748677    1       Not approved 2019-10-10
52748677    1       approved    2019-10-13
52748677    2       approved    2019-10-14

I Want to see:

MaterialNo  ToolID  Status         Asofdate
52748677    1       approved    2019-10-13
52748677    2       approved    2019-10-14

Answer 1

One solution that usually has very good performance is a correlated subquery:

select p.*
from [MfgDataCollector].[dbo].[PPAPStatus] p
where p.asof = (select max(p2.asof)
                from [MfgDataCollector].[dbo].[PPAPStatus] p2
                where p2.MaterialNo = p.MaterialNo and
                      p2.ToolID = p.ToolID
               );

For optimal performance, you want an index on (MaterialNo, ToolID, asof) .

Answer 2

I like using ROW_NUMBER with a TOP 1 WITH TIES trick here:

SELECT TOP 1 WITH TIES MaterialNo, ToolID, Status, Asofdate
FROM [MfgDataCollector].[dbo].[PPAPStatus]
ORDER BY ROW_NUMBER() OVER (PARTITION BY MaterialNo, ToolID ORDER BY Asofdate DESC);

Answer 3

Best option would be row_number()

   Select MaterialNo, ToolID, 
    PPAPStatus,AsofNow from (Select 
     MaterialNo, ToolID, 
      PPAPStatus,AsofNow, row_number() 
       over 
           (partition 
         by MaterialNo, ToolId, PPAStatus 
              order by 
            AsofNow desc) rn
       FROM [MfgDataCollector].[dbo]. 
       [PPAPStatus]
      ) t where t.rn=1

Answer 4

As of your requirement please find below query, Need your help.

;WITH CTE AS 
(
 SELECT *,ROW_NUMBER() OVER(PARTITION BY MaterialNo,ToolID ORDER BY Asofdate DESC) AS ROWNM  
 FROM [MfgDataCollector].[dbo].[PPAPStatus]
 )
 SELECT * FROM CTE WHERE ROWNM=1

Answer 5

Best option would be ROW_NUMBER() with no more complex logic with easy partition by fields.

Please find below query for as of requirement.

;WITH CTE AS
(
SELECT *, 
ROW_NUMBER() OVER (PARTITION BY MaterialNo,ToolID ORDER BY Asofdate DESC) AS ROWNM
FROM [MfgDataCollector].[dbo].[PPAPStatus]
)
SELECT * FROM CTE WHERE ROWNM=1