THE STUDY OF INDEXING TECHNIQUES ON OBJECT ORIENTED DATABASES

Abstract

The object-oriented database (OODB) has been becoming more important in the recent years. It can deal with a large amount of complex objects and relationships that relational database systems can not handle well. However the retrieval and update performance of an OODB depends on indexing techniques. In this paper, we study the indexing techniques on object-orented databases, based on the inheritance hierarchy and aggregation hierarchy. Given the access probability and the size of each class, we propose a cost function to evaluate the gain of building an index on the inheritance hierarchy. For the aggregation hierarchy, we use a path-catenation technique to evaluate how to build index files on classes, Through the experiments, we found our methods have betterretrieval performance than most ones proposed before.