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    <p>You are mixing things here. You are talking about collections, but you don't seem to use LINQ to objects but you are querying a database. </p> <p><strong>LINQ to objects:</strong><br> <a href="http://msdn.microsoft.com/en-us/library/bb534972.aspx" rel="noreferrer"><code>Enumerable.Any</code></a> and <a href="http://msdn.microsoft.com/en-us/library/bb549039.aspx" rel="noreferrer"><code>Enumerable.FirstOrDefault</code></a> should perform the same, because their code is near identical:</p> <p><code>FirstOrDefault</code>: </p> <pre><code>foreach (TSource source1 in source) { if (predicate(source1)) return source1; } return default (TSource); </code></pre> <p><code>Any</code>:</p> <pre><code>foreach (TSource source1 in source) { if (predicate(source1)) return true } return false; </code></pre> <p><strong>LINQ to some database:</strong><br> You are using Entity Framework, LINQ to SQL or NHibernate and use <a href="http://msdn.microsoft.com/en-us/library/bb534338.aspx" rel="noreferrer"><code>Queryable.Any</code></a> and <a href="http://msdn.microsoft.com/en-us/library/bb549141.aspx" rel="noreferrer"><code>Queryable.FirstOrDefault</code></a> on the corresponding data context.<br> In this case, there are really no collections, because these calls are not executed on in memory objects but translated to SQL. </p> <p>This means, the performance difference stems from how the LINQ provider translates the code to SQL, so the best would be to first check the statements created. Are they equivalent? Or are they very different (<code>select count(0) from X</code> vs. <code>select top 1 from X</code>)? Than the difference might lie in the query optimizer of the DB, indexes and what not...</p>
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    1. POPerformance of LINQ Any vs FirstOrDefault != null
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    1. USDaniel Hilgarth
    1. USDaniel Hilgarth
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      1. VTUpMod
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    1. COYou have a point here. We do DB queries by use of Entity and store the tables in collections. Then we iterate through those collections to extracting the data we want using LINQ.
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      1. USJimi
    2. CO@Jimi: I don't understand your comment, sorry. Maybe you want to rephrase or expand it.
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      1. USDaniel Hilgarth
    3. COHope I made it clearer.
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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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