An object-oriented database design for improved performance

Object-oriented databases (OODBs) are known to be rich in functionality but poor in performance. One of the important factors that affect performance is the physical database design. We developed a methodology for the design of an efficient storage structure of OODB that minimizes the database opera ting costs. The input for our method is the logical OODB schema and set of user transactions of retrieval and update types. The output of our method i s the determination of which instance variables should be inherited from di rect and indirect superclasses and stored in which subclasses. We used a ge netic algorithm (GA) to solve this intractable problem. The methodology was applied on a university database. Compared to previous storage models, the storage model produced with our methodology showed database performance im provement ranging from 26% to 31%, on the average. Our results demonstrate a cost-effective storage structure design that boosts the operating perform ance of OODBs. (C) 2001 Published by Elsevier Science B.V.