RE: Get the overall status of a particular product

SSC Guru

Points: 186127

October 2, 2012 at 9:10 am

Smash125 (10/2/2012)
How about this one correct me if i am wrong
;WITH C AS
(
SELECT *,ROW_NUMBER() OVER(PARTITION BY Status ORDER BY Product) AS Rn FROM #TestData
),
C1 AS
(
SELECT *,MIN(Rn)OVER(PARTITION BY Status) MinRn FROM C
)
SELECT Product,Status FROM C1 WHERE Rn=MinRn
ORDER BY Product ASC

Yes, it's wrong. The partition should be Product, not status:

;With TestData (Product,Parts,Status) AS (

SELECT 'Laptop1','mouse','OK' UNION ALL

SELECT 'Laptop1','screen','OK' UNION ALL

SELECT 'Laptop1','button','PASS' UNION ALL

SELECT 'Laptop2','mouse','OK' UNION ALL

SELECT 'Laptop2','screen','OK' UNION ALL

SELECT 'Laptop2','button','NOT OK' UNION ALL

SELECT 'Laptop3','button','OK' UNION ALL

SELECT 'Laptop3','screen','PASS' UNION ALL

SELECT 'Laptop3','mouse','PASS' UNION ALL

SELECT 'Laptop4','mouse','PASS' UNION ALL

SELECT 'Laptop5','button','PASS' UNION ALL

SELECT 'Laptop5','screen','PASS' UNION ALL

SELECT 'Laptop5','mouse','PASS' ),

C AS (SELECT *,ROW_NUMBER() OVER(PARTITION BY Status ORDER BY Product) AS Rn FROM TestData),

C1 AS (SELECT *,MIN(Rn)OVER(PARTITION BY Status) MinRn FROM C)

SELECT Product, Status, Rn, MinRn

FROM C1 --WHERE Rn=MinRn

ORDER BY Product ASC, Status

^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}

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