Issue No. 03 - May/June (1998 vol. 10)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/69.687974
<p><b>Abstract</b>—We present a new access method, called the path dictionary index (PDI) method, for supporting nested queries on object-oriented databases. PDI supports object traversal and associative search, respectively, with a path dictionary and a set of attribute indexes built on top of the path dictionary. We discuss issues on indexing and query processing in object-oriented databases; describe the operations of the new mechanism; develop cost models for its storage overhead and query and update costs; and compare the new mechanism to the path index method. The result shows that the path dictionary index method is significantly better than the path index method over a wide range of parameters in terms of retrieval and update costs and that the storage overhead grows slowly with the number of indexed attributes.</p>
Object-oriented database, aggregation hierarchy, index method, file structure, nested query.
D. L. Lee and W. Lee, "Path Dictionary: A New Access Method for Query Processing in Object-Oriented Databases," in IEEE Transactions on Knowledge & Data Engineering, vol. 10, no. , pp. 371-388, 1998.