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    <p>The type is different because your <code>newElement.ElementToComponentMappings</code> is collection but your query returns only single instance.</p> <p>You can try to use this:</p> <pre><code>context.ContextOptions.LazyLoadingEnabled = false; var newElement = (from c in context.ModelElements where c.ModelID == modelID &amp;&amp; c.ElementNo == modelElementNo select c).FirstOrDefault(); var mapping = (from m in context.ElementToComponentMappings where m.ModelID == modelID &amp;&amp; m.ElementNo == modelElementNo &amp;&amp; m.version == version select m).FirstOrDefault(); // now check if newElement.ElementToComponentMappings contains your single item </code></pre> <p>You can also try to use this:</p> <pre><code>context.ContextOptions.LazyLoadingEnabled = false; var newElement = (from c in context.ModelElements where c.ModelID == modelID &amp;&amp; c.ElementNo == modelElementNo select c).FirstOrDefault(); ((EntityCollection&lt;ElementToComponentMappings&gt;)newElement.ElementToComponentMappings) .CreateSourceQuery() .FirstOrDefault(m.version == version); // You don't need to check FKs here // now check if newElement.ElementToComponentMappings contains your single item </code></pre> <p>Neither of these methods works if your type is proxied and lazy loading is enabled because this expected automatic relation fixup will not mark navigation property as loaded (if you have lazy loading enabled next access to the property will trigger lazy loading and load all other entities).</p>
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    1. POEntityFramework/LINQ - get filtered content from associated table/type
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    1. USLadislav Mrnka
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    1. COThanks for your input, unfortunately not quite there yet: In your first suggestion, where does the newElement.ElementToComponentMappings property get set? In your second suggestion, I get an error that ElementToComponentMappings does not contain definition for FirstOrDefault, and the best extension method overload has invalid arguments. Regarding the type difference, you're right that ElementToComponentMappings is a collection - does that mean I should call ToList instead at some point?
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    2. COIn the first case it is a trick. If everything is correctly configured you don't need to set that property. It should be automatically populated. In second case it is strange. `CreateSourceQuery` should return `ObjectQuery` which is implementation of `IQueryable` and it offers `FirstOrDefault`. Your way with `ToList` will work only if your entity is not proxied, otherwise you will get some error that you cannot assign a new collection to navigation property.
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      1. USLadislav Mrnka
    3. CO+1 for the useful tips, tricks, and insights. In the end it I couldn't get this approach to work, so did it another way.
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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