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<h1>LINQ Examples</h1>
<p>In order to learn like, take a look a the LINQ-resources and tutorials out on the Internet. For example the <a href="http://msdn.microsoft.com/en-us/library/bb397926.aspx" target="_blank">LINQ-Overview at MSDN</a> or at <a href="http://msdn.microsoft.com/en-us/vcsharp/aa336746.aspx" target="_blank">this example-collection.</a> Here are a few db4o LINQ examples.</p>
<h2><a name="Simplest"></a>Simplest Possible Query</h2>
<p>This query just returns all persons.</p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">var allPersons = from Person p in container
select p;</pre>
<div class="codesnippet-meta">LinqExamples.cs: Simple query
<div class="codedownload"><a href="../../../CodeExamples/query/linq/Example-query-linq-csharp.zip" class="codedownload" MadCap:conditions="Primary.Online">Download Code</a></div><div class="codedownload copylink-marker" MadCap:conditions="Primary.Online"><a href="#copy">Copy Code</a></div></div>
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim allPersons = From p In container _
Select p</pre>
<div class="codesnippet-meta">LinqExamples.vb: Simple query
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<h2>Query For a Name</h2>
<p>This query searches for a person by name.</p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">var allPersons = from Person p in container
where p.Name.Equals("Joe")
select p;</pre>
<div class="codesnippet-meta">LinqExamples.cs: Query for name
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim allPersons = From p As Person In container _
Where p.Name.Equals("Joe") _
Select p</pre>
<div class="codesnippet-meta">LinqExamples.vb: Query for name
<div class="codedownload"><a href="../../../CodeExamples/query/linq/Example-query-linq-vb.zip" class="codedownload" MadCap:conditions="Primary.Online">Download Code</a></div><div class="codedownload copylink-marker" MadCap:conditions="Primary.Online"><a href="#copy">Copy Code</a></div></div>
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<h2>Query For a Certain Age</h2>
<p>This queries for a certain age.</p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">var allPersons = from Person p in container
where p.Age > 21
select p;</pre>
<div class="codesnippet-meta">LinqExamples.cs: Query with a constraint
<div class="codedownload"><a href="../../../CodeExamples/query/linq/Example-query-linq-csharp.zip" class="codedownload" MadCap:conditions="Primary.Online">Download Code</a></div><div class="codedownload copylink-marker" MadCap:conditions="Primary.Online"><a href="#copy">Copy Code</a></div></div>
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim allPersons = From p As Person In container _
Where p.Age > 21 _
Select p</pre>
<div class="codesnippet-meta">LinqExamples.vb: Query with a constraint
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<h2><a name="Sorting"></a><a name="kanchor9"></a>Sorting The Result Of A Query</h2>
<p>Sort the results of a query.</p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">var allPersons = from Person p in container
where p.Age > 21
orderby p.Name
select p;</pre>
<div class="codesnippet-meta">LinqExamples.cs: Use sorting on the query
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim allPersons = From p As Person In container _
Where p.Age > 21 _
Order By p.Name _
Select p</pre>
<div class="codesnippet-meta">LinqExamples.vb: Use sorting on the query
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<h2><a name="Get"></a>Get The IQueryable Interface</h2>
<p>You can get the .NET IQueryable interface for db4o</p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">IQueryable<Person> personQuerable = container.AsQueryable<Person>();
var adults = from p in personQuerable
where p.Age > 18
orderby p.Name
select p;</pre>
<div class="codesnippet-meta">LinqExamples.cs: Get a IQueryable-instance
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim personQuerable As IQueryable(Of Person) = container.AsQueryable(Of Person)()
Dim adults = From p In personQuerable _
Where p.Age > 18 _
Order By p.Name _
Select p</pre>
<div class="codesnippet-meta">LinqExamples.vb: Get a IQueryable-instance
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