Make documents without a life cycle state appear in parent content

when a document type has no life cycle attached, its state is null with the sql visible storage.
the query retriveing children tests that the state is not "deleted" and the document is not retrieved:

Yes, at the SQL level at the moment a NULL is stored if the lifecycle state was not initialized, and doing
x <operator> NULL
always returns NULL which is FALSE.

We'll have to make sure we never store NULL for the lifecycle state, what should we store if there's no lifecycle policy defined? "default" ? "" ?