A schema-oriented content management system, in particular to an apparatus and a method for storing and accessing data in a content management system which allows content schema evolution while maintaining operation based on already stored content data. A data processing apparatus for storing and accessing data in a content management system comprises a content object generation arrangement for generating content objects to store content data, wherein a content object comprises a plurality of property-value bindings, a content object storing arrangement for storing generated content objects, a content schema generation arrangement for generating an object-oriented content schema to model content data, a content schema storing arrangement for storing the generated content schema, and a content object accessing arrangement to access stored content objects by way of the stored content schema.