Aspect-oriented programming

The performance of relational database applications often suffers. The reason is that query optimizers require accurate statistics about data in the database in order to provide optimal query execution plans. Unfortunately, the computation of these statistics must be initiated explicitly (e.g., within application code), and computing statistics takes some time. Moreover, it is not easy to decide when to update statistics of what tables in an application. A well-engineered solution requires adding source code usually in many places of an application. The issue of updating the statistics for database optimization is a crosscutting concern. Thus we propose to use aspect-orientation to automate the calculation. We show how nicely the update functionality can be modularized in an aspect and how easy it is to specify the exact places and the time when statistics updates should be performed to speed up complex queries. Due to the automatic nature, computation takes place on time for complex queries, only when necessary, and only for stale tables. The implementation language for the automated aspect-oriented statistics update concern is AspectJ, a well known and mature aspect-oriented programming language. The approach can however be implemented in any other aspect-oriented language. Unlike in traditional object-oriented pattern solutions, e.g. using the interceptor pattern, we do not have to modify existing code.