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<h1><a name="kanchor4"></a>The Basic Operations</h1>
<P>The object container is the door to the database access. It's the starting point for all database operations.</P>
<h2><a name="AccessingDB"></a>Accessing a Database </h2>
<P>The object container is the interface for accessing the database. To open the database you pass the file-name to the object container factory. Normally you should open an object container when the application starts and close it when it is shuts down. </P>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">using (IObjectContainer container = Db4oEmbedded.OpenFile("databaseFile.db4o"))
{
// use the object container
}</pre>
<div class="codesnippet-meta">Db4oBasics.cs: Open the object container to use the database
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">' use the object container
Using container As IObjectContainer = Db4oEmbedded.OpenFile("databaseFile.db4o")
End Using</pre>
<div class="codesnippet-meta">Db4oBasics.vb: Open the object container to use the database
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<h2><a name="kanchor5"></a><a name="StoringObject"></a>Storing Objects</h2>
<P>Storing a object with db4o is extremely easy. Open the object container and pass your object to the store method and db4o will do the rest. There's no mapping required. db4o will read the class meta data, the read the object values with reflection and store the data.</P>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">using (IObjectContainer container = Db4oEmbedded.OpenFile("databaseFile.db4o"))
{
Pilot pilot = new Pilot("Joe");
container.Store(pilot);
}</pre>
<div class="codesnippet-meta">Db4oBasics.cs: Store a object
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Using container As IObjectContainer = Db4oEmbedded.OpenFile("databaseFile.db4o")
Dim pilot As New Pilot("Joe")
container.Store(pilot)
End Using</pre>
<div class="codesnippet-meta">Db4oBasics.vb: Store a object
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<h2><a name="Queries"></a>Queries </h2>
<p>Querying for objects is also easy. There are different query interfaces available with different benefits. <a href="querying.htm" target="" title="" alt="" class="MCXref" xrefformat="See "{paratext}"">See "Querying"</a></p>
<p MadCap:conditions="Primary..NET">The most natural query method is using <a href="querying/linq.htm">LINQ</a>. </p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">using (IObjectContainer container = Db4oEmbedded.OpenFile("databaseFile.db4o"))
{
var pilots = from Pilot p in container
where p.Name == "Joe"
select p;
foreach (var pilot in pilots)
{
Console.Out.WriteLine(pilot.Name);
}
}</pre>
<div class="codesnippet-meta">Db4oBasics.cs: Query for objects
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Using container As IObjectContainer = Db4oEmbedded.OpenFile("databaseFile.db4o")
Dim pilots = From p As Pilot In container Where p.Name = "Joe"
For Each pilot As Pilot In pilots
Console.Out.WriteLine(pilot.Name)
Next
End Using</pre>
<div class="codesnippet-meta">Db4oBasics.vb: Query for objects
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<h2><a name="UpdateObjects"></a>Update Objects</h2>
<p>Updating objects is also easy. First you query for the object which you want to update. Then you change the object and store it again in the database.</p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">using (IObjectContainer container = Db4oEmbedded.OpenFile("databaseFile.db4o"))
{
var pilot = (from Pilot p in container
where p.Name == "Joe"
select p).First();
pilot.Name = "New Name";
// update the pilot
container.Store(pilot);
}</pre>
<div class="codesnippet-meta">Db4oBasics.cs: Update a pilot
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Using container As IObjectContainer = Db4oEmbedded.OpenFile("databaseFile.db4o")
Dim pilot = (From p As Pilot In container Where p.Name = "Joe").First()
pilot.Name = "New Name"
' update the pilot
container.Store(pilot)
End Using</pre>
<div class="codesnippet-meta">Db4oBasics.vb: Update a pilot
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<h2><a name="DeleteObjects"></a>Delete Objects</h2>
<P>Use the delete-operation to delete objects.</P>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">using (IObjectContainer container = Db4oEmbedded.OpenFile("databaseFile.db4o"))
{
var pilot = (from Pilot p in container
where p.Name == "Joe"
select p).First();
container.Delete(pilot);
}</pre>
<div class="codesnippet-meta">Db4oBasics.cs: Delete a object
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Using container As IObjectContainer = Db4oEmbedded.OpenFile("databaseFile.db4o")
Dim pilot = (From p As Pilot In container Where p.Name = "Joe").First()
container.Delete(pilot)
End Using</pre>
<div class="codesnippet-meta">Db4oBasics.vb: Delete a object
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