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  1. PO
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    <p>The output is <code>2,4,6,8</code> because of <a href="http://msdn.microsoft.com/en-us/library/bb943859.aspx" rel="noreferrer">deferred execution</a>.</p> <blockquote> <p>The query is actually executed when the query variable is iterated over, not when the query variable is created. This is called deferred execution.</p> <p>-- Suprotim Agarwal, <a href="http://www.dotnetcurry.com/ShowArticle.aspx?ID=750" rel="noreferrer">"Deferred vs Immediate Query Execution in LINQ"</a></p> </blockquote> <p>There is another execution called <a href="http://msdn.microsoft.com/en-us/library/bb738633.aspx" rel="noreferrer">Immediate Query Execution</a>, which is useful for caching query results. From Suprotim Agarwal again:</p> <blockquote> <p>To force immediate execution of a query that does not produce a singleton value, you can call the <code>ToList(), ToDictionary(), ToArray(), Count(), Average()</code> or <code>Max()</code> method on a query or query variable. These are called conversion operators which allow you to make a copy/snapshot of the result and access is as many times you want, without the need to re-execute the query.</p> </blockquote> <p>If you want the output to be <code>2,4,6</code>, use <a href="http://msdn.microsoft.com/en-us/library/bb342261.aspx" rel="noreferrer"><code>.ToList()</code></a>:</p> <pre><code>var list = new List&lt;int&gt;{1,2,4,5,6}; var even = list.Where(m =&gt; m%2 == 0).ToList(); list.Add(8); foreach (var i in even) { Console.WriteLine(i); } </code></pre>
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    1. POHow does the following LINQ statement work?
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    1. USAtish Dipongkor
    1. USAtish Dipongkor
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    1. POHow does the following LINQ statement work?
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    1. COWould it only be executed when iterating or in other cases, too?
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      1. USSebastian
    2. COCount(), Max(), Avg(), Sum() and probably other methods that need to take the whole list into consideration, also cause evaluation of the query.
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      1. USKenned
    3. COI've often thought about having, say, 'filteredList' as a variable, rather than 'filterList()' as a method - the idea being, you iterate over it each time you want the list filtered, rather than calling a method. Might be an interesting, if unusual and perhaps imperfect performance-wise, method of doing things.
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      1. USKatana314
 

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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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