Get the whole ROW which has the MAX value for a column with join
I have exhausted my wit with this problem, so I bring the challenge to you:
--CREATING DATA:
DECLARE @CONTACTS TABLE (ID INT, NickName CHAR(10))
INSERT INTO @CONTACTS VALUES (1359,'John Smith')
INSERT INTO @CONTACTS VALUES (1360,'Ana Keller')
INSERT INTO @CONTACTS VALUES (1361,'Joshua Doe')
DECLARE @ENTERPRISES TABLE (ID INT, CON_ID INT, ASSOCIATION DATETIME)
INSERT INTO @ENTERPRISES VALUES (123,1359,Convert(datetime, '2000-10-09', 120))
INSERT INTO @ENTERPRISES VALUES (123,1360,Convert(datetime, '2000-02-21', 120))
INSERT INTO @ENTERPRISES VALUES (123,1361,Convert(datetime, '2000-04-09', 120))
--QUERYING THE DATA:
SELECT * FROM @CONTACTS C
JOIN @ENTERPRISES E ON C.ID = E.CON_ID
--THE RESULT SET OF MY DREAMS:
1359 John Smith 123 1359 2000-10-09
What I want is an entire row of the query before, but only the one that has the maximum ASSOCIATION date for e开发者_C百科ach Enterprise ID. This is only an example for the sake of clarity, my real query is much more complex, with much more columns and trillions of rows. I have tried
SELECT *,max(FOUNDING) OVER (PARTITION BY E.ID) FROM @CONTACTS C
JOIN @ENTERPRISES E ON C.ID = E.CON_ID
But it still brings all three rows. Other approaches were worse and led to the parser asking me to GROUP BY every column. I appreciate your help.
WITH cteMaxAssociation AS (
SELECT ID, CON_ID, ASSOCIATION,
ROW_NUMBER() OVER(PARTITION BY ID ORDER BY ASSOCIATION DESC) AS RowNum
FROM @ENTERPRISES
)
SELECT C.ID, C.NickName, ma.ID, ma.CON_ID, ma.ASSOCIATION
FROM @CONTACTS C
INNER JOIN cteMaxAssociation ma
ON C.ID = ma.CON_ID
AND ma.RowNum = 1
SELECT *
FROM @CONTACTS C
JOIN @ENTERPRISES E ON C.ID = E.CON_ID
(SELECT max(association) as maxdate, CON_ID , ID, ASSOCIATION
FROM Entpresises
GROUP BY CON_ID ) maxresults
WHERE E.ID = maxresults.ID
AND E.ASSOCIATION = maxresults.ASSOCIATION ;
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