An Optimization Algorithm for Queries With Expensive Multimedia Restrictions
In this paper, the authors discuss a problem on query optimization for multimedia data management systems, i.e., how to optimize queries with expensive multimedia restrictions. Because of the low expenses, selections have typically been handled in traditional query optimization schemes by the "Pushdown" strategy so as to reduce subsequent join costs. In a multimedia database system, however, selections generally contain expensive multimedia restrictions. Therefore, the assumption of traditional query optimization does not come into existence, and the optimization about multimedia queries has to be restudied.