A Multi-Granular Lock Model for Distributed Object Oriented Databases Using Semantics

摘要

In object oriented databases, transactions may make simultaneous requests to do design time access and runtime access of resources. Concurrency control on the transactions can be implemented by using Multi granular lock models. Though several semantics based multi granular lock models have been proposed in the literature for object-oriented databases, they provide fine granularity of resources for runtime requests. However they have not fully utilized the semantics of object-oriented concepts to provide fine granularity of design time requests. In the proposed semantic based multi granular lock model, various dependencies of objects are exploited to exercise concurrency control. The dependencies among objects participating in the system can be inferred through their relationships such as inheritance, composition etc, with other objects participating in the domain. The proposed lock model uses these dependencies in defining lock modes for design time requests, which will provide fine granularity. It also utilizes these dependencies to provide better concurrency control for transactions modifying class relationships using Relationship Vectors (RV).