Title :
An improved algorithm for the incremental recomputation of active relational expressions
Author :
Griffin, Timothy ; Libkin, Leonid ; Trickey, Howard
Author_Institution :
AT&T Bell Labs., Murray Hill, NJ, USA
Abstract :
Qian and Wiederhold (1991) presented an algorithm for the incremental recomputation of relational algebra expressions that was claimed to preserve a certain minimality condition. This condition guarantees that the incremental change sets do not contain any unnecessary tuples; so, redundant computations are not performed. We show that, in fact, their algorithm violates this condition. We present an improved algorithm that does preserve this notion of minimality
Keywords :
active databases; relational algebra; relational databases; active relational expressions; change propagation; incremental change sets; incremental recomputation; minimality condition; relational algebra expressions; view maintenance; Algebra; Relational databases; Transaction databases;
Journal_Title :
Knowledge and Data Engineering, IEEE Transactions on