The COCOON object model

Abstract

The COCOON model was intended to extend the concepts of relational database managernent systems (DBMSs) beyond nested relational to object-oriented ones. Key characteristics of COCOON and its database language COOL are: generic, set-oriented query and update operators sirnilar to relational algebra and SQL updates, respectively; object-preserving semantics of query operators, which allows for the definition of updatable views; update operations that keep model-inherent integrity constraints consistent; a separation of the two aspects of programming language "classes": type vs. collection; predicative description of collections, sirnilar to "defined concepts" in KL-One-like knowledge representation languages; automatic classification of objects and views (positioning in the dass hierarchy).