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POSQL to combine data for single row per object
 

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    <p>I know this must be a common problem, but I'm not sure where to go. This occurs a few times inside a big nasty query, so here is the problem simplified. I just want one row per object, but the null on ColorOther gives me two rows. </p> <p>I can think of a few things to try wrapping a query around this, but there must be something simpler... I'm off to read up on pivots.</p> <p>Table structure</p> <pre><code>CREATE TABLE [dbo].[Colors]( [ColorId] [int] IDENTITY(1,1) NOT NULL, [ColoredObjectId] [int] NOT NULL, [ColorCode] [int] NOT NULL, [ColorOther] [nvarchar](50) NULL, CONSTRAINT [PK_Colors] PRIMARY KEY CLUSTERED ([ColorId] ASC) </code></pre> <p>Source data</p> <pre><code>ColorId ColoredObjectId ColorCode ColorOther ----------- --------------- ----------- ---------- 1 1 1 NULL 2 1 2 NULL 3 1 4 purple 4 2 2 NULL 5 2 3 NULL 6 2 4 orange 7 3 1 NULL 8 3 3 NULL 9 3 4 green </code></pre> <p>Query</p> <pre><code>SELECT ColoredObjectId , ColorOther , MAX(CASE WHEN ColorCode = 1 THEN 1 ELSE 0 END) AS Yellow, MAX(CASE WHEN ColorCode = 2 THEN 1 ELSE 0 END) AS Red , MAX(CASE WHEN ColorCode = 3 THEN 1 ELSE 0 END) AS Blue , MAX(CASE WHEN ColorCode = 4 THEN 1 ELSE 0 END) AS Other FROM Colors GROUP BY ColoredObjectId, ColorOther </code></pre> <p>Output</p> <pre><code>ColoredObjectId ColorOther Yellow Red Blue Other --------------- ---------- ----------- ----------- ----------- ----------- 1 NULL 1 1 0 0 1 purple 0 0 0 1 2 NULL 0 1 1 0 2 orange 0 0 0 1 3 NULL 1 0 1 0 3 green 0 0 0 1 </code></pre> <p>Desired output</p> <pre><code>ColoredObjectId ColorOther Yellow Red Blue Other --------------- ---------- ----------- ----------- ----------- ----------- 1 purple 1 1 0 1 2 orange 0 1 1 1 3 green 1 0 1 1 </code></pre>
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    1. COIt looks like its not only the ColorOther NULL that is giving you two rows, the Other column has different values for your aggregation, so they are two different set of rows. What is the desired output for your query?, and what version of SQL Server are you using?
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      1. USLamak
    2. COWhat do NULL ColorOther values really mean? Are the legitimate rows you want to see?
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      1. USSparky
    3. COJust remove `ColorOther` from the `group by`
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      1. USMartin Smith
 

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