Question

I have the following query

    SELECT  P.ID, MAX(ENTERDATE) as ENTERDATE, MAX(B.CostID) as CostID 
    FROM Protocol P JOIN BANK B ON P.ID= B.ID                                   
    group by P.ID

I need to find out what the Maximum enterdate was along with the corresponding CostID but I do not want to use MAX(B.CostID) but I am forced
to do so as I have a group by P.ID and all other fields need to have some kind of aggregate. How do I say group by P.ID and show me the max(enterdate) but give me the corresponding CostID for that Enterdate?

Answer 1

 SELECT  P.ID, 
         ENTERDATE  = MAX(p.ENTERDATE), 
         CostID     = (SELECT CostID FROM Bank WHERE ID = p.ID)
  FROM  Protocol P                   
  group by P.ID

OR something like

SELECT  t.*,
        CostID
  FROM  Bank b
        JOIN (
                SELECT  P.ID, 
                         ENTERDATE  = MAX(p.ENTERDATE)
                   FROM  Protocol P                   
                   group by P.ID                
             ) t ON t.ID = b.ID