Store entity as base type document
===

I have a `BaseEntity` and a set of derived entities: `DerivedEntity1`, `DerivedEntity2`, etc.. Every derived document is stored to its collection. Is there any way to retrieve all documents which are derived from base type? Something like that:

    var baseEntities = documentSession.Query<BaseEntity>().ToList();

I have found some ways but they require to know all derived entities types. It doesn't suite me as in my case these types are generated kind of dynamically.