Docs: Update Dynamic_Default_Fields.md (silverstripe#8941)

docs/en/02_Developer_Guides/00_Model/How_Tos/Dynamic_Default_Fields.md

@@ -1,7 +1,27 @@
-# Dynamic Default Values
+# Default Values and Records
 
-The [DataObject::$defaults](api:SilverStripe\ORM\DataObject::$defaults) array allows you to specify simple static values to be the default values when a
-record is created, but in many situations default values need to be dynamically calculated. In order to do this, the
+## Static Default Values
+The [DataObject::$defaults](api:SilverStripe\ORM\DataObject::$defaults) array allows you to specify simple static values to be the default values when a record is created.
+
+A simple example is if you have a dog and by default it's bark is "Woof":
+```php
+use SilverStripe\ORM\DataObject;
+
+class Dog extends DataObject 
+{
+    private static $db = [
+        'Bark' => 'Varchar(10)',
+    ];
+
+    private static $defaults = [
+        'Bark' => 'Woof',
+    ];
+}
+```
+
+## Dynamic Default Values
+
+In many situations default values need to be dynamically calculated. In order to do this, the
 [DataObject::populateDefaults()](api:SilverStripe\ORM\DataObject::populateDefaults()) method will need to be overloaded.
 
 This method is called whenever a new record is instantiated, and you must be sure to call the method on the parent
@@ -38,3 +58,24 @@ public function populateDefaults()
     parent::populateDefaults();
 }
 ```
+
+## Static Default Records
+The [DataObject::$default_records](api:SilverStripe\ORM\DataObject::$default_records) array allows you to specify default records created on dev/build.
+
+A simple example of this is having a region model and wanting a list of regions created when the site is built:
+```php
+use SilverStripe\ORM\DataObject;
+
+class Region extends DataObject 
+{
+    private static $db = [
+        'Title' => 'Varchar(45)',
+    ];
+
+    private static $default_records = [
+        ['Title' => 'Auckland'],
+        ['Title' => 'Coromandel'],
+        ['Title' => 'Waikato'],
+    ];
+}
+```