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sqlsql-servermedian

How can I exclude zeroes in my Median calculation in this specific context?


I am using SQL Server 2014 and I have the following T-SQL query to calculate Median values. However, I want my Median syntax (Percentile_cont) to exclude zeroes when performing the calculation. How can I do this?

CREATE TABLE #MyTempTable (Id int, Market nvarchar(50), [F&B] numeric (19,4) , SPA numeric (19,4))

INSERT INTO #MyTempTable
VALUES
(200, 'UK', 200, 0),
(210, 'UK', 150, 300),
(236, 'FRANCE', 60, 450),
(237, 'FRANCE', 120, 0),
(265, 'UK', 400, 100),
(270, 'FRANCE', 0, 140)

SELECT 
DISTINCT [Market],    
PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY ([F&B])) OVER (PARTITION BY [Market]) AS 'MEDIAN_F&B',
PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY ([SPA])) OVER (PARTITION BY [Market]) AS 'MEDIAN_SPA'

FROM #MyTempTable

Current output:

Market  MEDIAN_F&B  MEDIAN_SPA
FRANCE    60            140
UK       200            100

Expected OutPut:

expected ouput


Solution

  • Try

    SELECT [Market], [MEDIAN_F&B], [MEDIAN_SPA]
    FROM 
        (SELECT 
        DISTINCT [Market], CASE [F&B] WHEN 0 THEN 0 ELSE 1 END + CASE [SPA] WHEN 0 THEN 0 ELSE 1 END g,   
        PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY ([F&B])) OVER (PARTITION BY [Market], CASE [F&B] WHEN 0 THEN 0 ELSE 1 END ) AS [MEDIAN_F&B],
        PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY ([SPA])) OVER (PARTITION BY [Market], CASE [SPA] WHEN 0 THEN 0 ELSE 1 END ) AS [MEDIAN_SPA]
        FROM #MyTempTable    
    ) t
    WHERE g=2