Toward a Query Language on Simulation Mesh Data: an Object-Oriented Approach

Byung Lee, Robert Snapp
Department of Computer Science
University of Vermont
{bslee, snap}@cs.uvm.edu

Ron Musick*
iKuni, Inc
Palo Alto, CA 94304
musick@ikuni.com

Abstract

As simulation is gaining popularity as an inexpensive means of experimentation in diverse fields of industry and government, the attention to the data generated by scientific simulation is also increasing. Scientific simulation generates mesh data, i.e. data configured in a grid structure, in a sequence of time steps. Its model is complex - understanding it involves mathematical topology and geometry in addition to fields (in the relational sense). Moreover, there is no query languaged developed on mesh data at all. These are what we address in this paper. We develop a comprehensive model of mesh data in an object-oriented manner, propose a set of primitive algebraic operators, show their object-oriented implementation, and demonstrate that the well-known object query language ODMG OQL is powerful enough to express queries on mesh data, whether the queries are on mesh topology, geometry, fields, of a combination of them. Finally, we discuss some physical implementation issues pertinent to executing queries efficiently.

To Appear in

International Conference on Database Systems for Advanced Applications (DASFA), Hong Kong, April 2001.

Look at the Paper (pdf.gz)

* Work done while author at
Center for Applied Scientific Computing
Lawrence Livermore National Laboratory
P.O. Box 808, L-561, Livermore, CA 94551