Improved query builder section

-> Added a new section about binding params to the query
-> Added a short note on how to use $qb->expr()->in() with string values

manual/en/query-builder.txt

@@ -72,6 +72,56 @@ This method is the responsable to build every piece of DQL. It takes 3 parameter
        ->add('where', 'u.id = ?1')
        ->add('orderBy', 'u.name ASC');
 
+++++ Binding parameters to your query
+
+Doctrine supports dynamic binding of parameters to your query, similar to preparing queries. You can use both strings and numbers as placeholders, although both have a slightly different syntax. Binding parameters can simply be achieved as follows:
+
+	[php]
+    // $qb instanceof QueryBuilder
+    
+    // example6: how to define: "SELECT u FROM User u WHERE u.id = ? ORDER BY u.name ASC" using QueryBuilder string support
+    $qb->add('select', 'u')
+       ->add('from', 'User u')
+       ->add('where', 'u.id = ?1')
+       ->add('orderBy', 'u.name ASC');
+	   ->setParameter(1, 100); // Sets ?1 to 100, and thus we will fetch a user with u.id = 100
+
+You are not forced to enumerate your placeholders as the alternative syntax is available:
+
+
+	[php]
+    // $qb instanceof QueryBuilder
+    
+    // example6: how to define: "SELECT u FROM User u WHERE u.id = ? ORDER BY u.name ASC" using QueryBuilder string support
+    $qb->add('select', 'u')
+       ->add('from', 'User u')
+       ->add('where', 'u.id = :identifier')
+       ->add('orderBy', 'u.name ASC');
+	   ->setParameter('identifier', 100); // Sets :identifier to 100, and thus we will fetch a user with u.id = 100
+
+Note that numeric placeholders start with a ? followed by a number while the named placeholders start with a : followed by a string.
+
+If you've got several parameters to bind to your query, you can also use setParameters() instead of setParameter() with the following syntax:
+
+    [php]
+	// $qb instanceof QueryBuilder
+    
+    // Query here...
+	$qb->setParameters(array(1 => 'value for ?1', 2 => 'value for ?2', 'whatever' => 'your value for :whatever'));
+
+
+Getting already bound parameters is easy - simply use the abovementioned syntax with "getParameter()" or "getParameters()":
+
+    [php]
+	// $qb instanceof QueryBuilder
+    
+    // See example above
+	$params = qb->getParameters(array(1, 2, 'whatever'));
+	// Equivalent to
+	$param  = array($qb->getParameter(1), $qb->getParameter(2), $qb->getParameter('whatever'));
+
+Note: If you try to get a parameter that was not bound yet, getParameter() simply returns NULL.
+
 ++++ Expr\* classes
 
 When you call `add()` with string, it internally evaluates to an instance of `Doctrine\ORM\Query\Expr\Expr\*` class.
@@ -197,6 +247,8 @@ Here it is a complete list of supported helper methods available:
         public function not($restriction); // Returns Expr\Func instance
         
         // Example - $qb->expr()->in('u.id', array(1, 2, 3))
+		// Make sure that you do NOT use something similar to $qb->expr()->in('value', array('stringvalue')) as this will cause Doctrine to throw an Exception.
+		// Instead, use $qb->expr()->in('value', array('?1')) and bind your parameter to ?1 (see section above)
         public function in($x, $y); // Returns Expr\Func instance
     
         // Example - $qb->expr()->notIn('u.id', '2')
@@ -353,4 +405,4 @@ Here is a complete list of helper methods in `QueryBuilder`:
 
         // Example - $qb->addOrderBy('u.firstName')
         public function addOrderBy($sort, $order = null); // Default $order = 'ASC'
-    }
+    }