VCR Indexing for Fast Event Matching for Highly-Overlapping Range Predicates

Fast matching of events against a large number of range predicates is important for many applications. An efficient predicate index is usually needed. It is difficult to build an effective index for multidimensional range predicates. It is even more challenging if the predicates are highly overlapping, as they usually are for many applications. We present a novel VCR indexing scheme for highly-overlapping 2D range predicates. VCR stands for virtual construct rectangle. Each predicate is decomposed into one or more VCRs, which are then considered to be activated. The predicate ID is then stored in the ID lists associated with these activated VCRs. Event matching is conceptually simple. For each event point, the search result is stored in the ID lists associated with the activated VCRs that cover the event point. However, it is computationally nontrivial to identify the activated covering VCRs. We define a covering VCR set for each event point and identify two important properties. Based on these properties, an efficient algorithm is presented for fast event matching. We also present an overlapped decomposition (OD) to reduce the storage overhead. Simulations are conducted to study the performance of VCR indexing.

By: Kun-Lung Wu, Shyh-Kwei Chen, Philip S. Yu

Published in: RC22947 in 2003


This Research Report is available. This report has been submitted for publication outside of IBM and will probably be copyrighted if accepted for publication. It has been issued as a Research Report for early dissemination of its contents. In view of the transfer of copyright to the outside publisher, its distribution outside of IBM prior to publication should be limited to peer communications and specific requests. After outside publication, requests should be filled only by reprints or legally obtained copies of the article (e.g., payment of royalties). I have read and understand this notice and am a member of the scientific community outside or inside of IBM seeking a single copy only.


Questions about this service can be mailed to .