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POFinding Overlapping Interests in LINQ
 

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    <p>I have a model where a place has some descriptions, those descriptions are associated with interests (place.description.interests). A user looking at the view for a place is represented in the model as a user, who also has a number of interests.</p> <p>What I want to do is sort the description by overlapping interests (including zero overlapping), where my current Linq is:</p> <pre><code>place dest = (from p in _db.places where p.short_name == id select p).Single(); return View(dest); </code></pre> <p>Now the following will do what I want in SQL on the schema in question:</p> <pre><code>SELECT COUNT(interest_user.user_id) AS matches, description.* FROM description JOIN interest_description ON description.user_id = interest_description.user_id AND description.place_id = interest_description.place_id JOIN interest ON interest_description.interest_id = interest.interest_id LEFT JOIN interest_user ON interest.interest_id = interest_user.interest_id WHERE interest_user.user_id = 2 AND description.place_id = 1 GROUP BY interest_description.user_id, interest_description.place_id ORDER BY matches DESC </code></pre> <p>But I'm too new to Linq to know how I would handle this correctly. Ideally I could pull this off while still passing in a strongly typed model.</p> <p>I have managed this so far:</p> <pre><code>var desc = from d in _db.descriptions from i in d.interests from u in i.users.DefaultIfEmpty() where d.place_id == PlaceID &amp;&amp; (u.user_id == userID </code></pre> <p>(PlaceID and UserID are arguments passed to the controller that is managing this).</p> <p>Simply put, given this linq, I just need to return d, ordered by a count of i.</p> <p><strong>my model</strong> <img src="https://i.stack.imgur.com/lu2Yw.png" alt="enter image description here"></p>
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    1. USMike Hillyer
    1. USMike Hillyer
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    1. COCan u give example of input data and what result should be for them?
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      1. USPiotr Auguscik
    2. COOk, so I have a place with ID of 1, and a user with ID of 1. My user has interests 1,2,4. The place has descriptions 1,2,3 where description 1 has interests 1,2 and description 2 has interests 2,3 and description 3 has interests 1,2,3,4. When user 1 views place 1, the descriptions should be sorted 3,1,2 because 3 has three overlapping interests, 1 has two overlapping interests, 2 has one overlapping interest.
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      1. USMike Hillyer
 

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