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POLinq orderby sum of sublist item compared to mainlist item
 

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  1. POLinq orderby sum of sublist item compared to mainlist item
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    <p>I have a issue I havn't yet been able to find a solution on. To simplify the issue: I have two SQL tables and I'm using LinQ to SQL. The two tables represents Courses, where CourseType contains CourseName and TotalSpots, and CourseInstance contains CourseDate, AmountSignedUp and a refrence to CourseType. There's a one to many relation between CourseType and CourseInstance.</p> <p>Now what I need help with is the Linq query/Lambda expression to sort both CourseType and CourseInstance (if it's posible). I want the CourseType to be sorted after how many in total free spots (calculated from every CourseInstance under CourseType; CourseType.TotalSpots - CourseInstance.SignedUp), where the CourseType with most free spots shows first. I want CourseInstance to be sorted simlar, by how many free spots that CourseInstance has (CourseType.TotalSpots - CourseInstance.AmountSignedUp).</p> <p>I can't get my head around how to solve this. I've looked at simlar questions and issue and this is what I've made so far, just to give a basic idea:</p> <p>Edit: I've done this code so far which will sort the CourseType correctly. I'm not sure how I can get the CourseInstance sublist sorted (CourseType.CourseInstance). I guess I'll have to do it later in the code when I'm converting it to a list unless someone has a good solution for this. I could do it as Arion suggested, why I'll mark his answer.</p> <pre><code>var result= ( from c in _db.CourseType orderby ((c.TotalSpots * c.CourseInstance.Count) - c.CourseInstance.Sum( ci =&gt; (ci.AmountSignUp ?? 0))) descending select c ); </code></pre>
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    1. USArne H. Bitubekk
    1. USArne H. Bitubekk
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
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      1. POLinq orderby sum of sublist item compared to mainlist item
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    1. This table or related slice is empty.
 

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