Implementation and Performance Analysis of Incremental Equations for Nested Relations

Incremental view maintenance is widely preferred to view recomputation when an update to a base relation is small in size. The update size becomes an important concept for measuring the cheap performance of the incremental maintenance. In this paper, we investigate what is the limit of the update size for the incremental maintenance. When the size of an update exceeds the limit, the incremental maintenance is no longer cheaper than the view recomputation. The investigation is based on incremental equations for operators in the nested relational model. We implement these equations in the Informix Universal Database Server. We propose a cost model for the performance analysis of the equations. We analyze the factors aecting the incremental maintenance and nally we study the maintenance limit for each operator and for the combination of the operators