By default db4o only stores changes on the updated object, but not the changes on referenced objects. With a higher update-depth db4o will traverse along the object graph to a certain depth and update all objects. See "Update Concept". You can also specify this globally.
IEmbeddedConfiguration configuration = Db4oEmbedded.NewConfiguration(); configuration.Common.ObjectClass(typeof (Person)).UpdateDepth(2);
Dim configuration As IEmbeddedConfiguration = Db4oEmbedded.NewConfiguration() configuration.Common.ObjectClass(GetType(Person)).UpdateDepth(2)