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The Object-Oriented Database System Manifesto M. Atkinson, F. Bancilhon, D. DeWitt, K. Dittrich, D. Maier & S. Zdonik DOOD’89 Kyoto Japan Motivation for paper ”Proposition” paper Establish common ground for further development in Object-Oriented Database Systems (OODBS). Establish guidelines for separating object oriented databases and non-object oriented databases. The paper were meant to function as a roadmap for those doing OODBS research. Paper outline: What is needed in an OODBS? Mandatory – Functionality necessary for an OODBS Optional – Interesting functionality able to expand the usability of the OODBS Open – Design issues; Few right and / or wrong answers exists. Mandatory properties (1) Complex objects Unique object identity Minimum: Set, list and tuples Orthogonal constructors Equal or the same object? Update and sharing issues Encapsulation Only operations should be visible Methods for overriding encapsulation is necessary. Mandatory properties (2) Types and classes Class or type hierarchies Type or class hierarchy must be supported. Overriding, overloading and late binding Types or classes are meant to replace database schemas. A method is defined at the most general level (overriding) and can be redefined for subclasses (overloading). Which version of method to be used is determined at runtime (late binding). Computational completeness Any computational function can be expressed using the DML of the database. Mandatory properties (3) Extensibility Possibility for defining new types. New types must be handled as predefined types. Persistence Any object can become persistent. Mandatory properties (4) Secondary storage management Concurrency Serializability must be offered. Recovery Invisible database mechanisms to allow for reasonable performance. Must be able to recover for hardware and software failure. Ad Hoc Query Facility Must be high level, efficient and application independent. Optional properties Multiple inheritance Type checking and type inferencing Distribution Design transactions Versions Open choices Programming paradigm Representation system Type system Uniformity Conclusion The authors invite to further discussion based on the suggested requirements for OODBS.