Summary: On Two­Dimensional Indexability and
Optimal Range Search Indexing
(Extended Abstract)
Lars Arge \Lambda Vasilis Samoladas y Jeffrey Scott Vitter z
Abstract
In this paper we settle several longstanding open problems in
theory of indexability and external orthogonal range search­
ing. In the first part of the paper, we apply the theory of
indexability to the problem of two­dimensional range search­
ing. We show that the special case of 3­sided querying can
be solved with constant redundancy and access overhead.
From this, we derive indexing schemes for general 4­sided
range queries that exhibit an optimal tradeoff between re­
dundancy and access overhead.
In the second part of the paper, we develop dy­
namic external memory data structures for the two query
types. Our structure for 3­sided queries occupies O(N=B)
disk blocks, and it supports insertions and deletions
in O(log B N) I/Os and queries in O(log B N + T=B)
I/Os, where B is the disk block size, N is the num­

Source: Arge, Lars - Department of Computer Science, Aarhus Universitet
Samoladas, Vasilis - Department of Electronics and Computer Engineering, Technical University of Crete

Collections: Computer Technologies and Information Sciences