913aca9a_ent_repository___Henri_Bergius__CouchDB
[feature] content type system [JCR / Jackrabbit] In JCR structured or unstructured nodes are supported and can be mixed at will in a content tree. [Midgard] Content types are defined in MgdSchema types. All content must be stored to an MgdSchema type, but types can be extended on content instance level using the "parameter" triplets [CouchDB] 
Type-free
What is a content repository - Henri Bergius
CouchDB