Path: utzoo!utgpu!water!ylfink
From: ylfink@water.waterloo.edu (ylfink)
Newsgroups: ont.events,uw.talks
Subject: Computer Science Colloquium, University of Waterloo
Keywords: Dr. Hans-Peter Kriegel, University of Bremen, West Germany, (Visiting Professor at the University of Waterloo) will speak on ``Spatial Access Methods  based on Dynamic Hashing''.
Message-ID: <1812@water.waterloo.edu>
Date: 6 Sep 88 12:36:07 GMT
Distribution: ont
Organization: U of Waterloo, Ontario
Lines: 36



DEPARTMENT OF COMPUTER SCIENCE
UNIVERSITY OF WATERLOO
SEMINAR ACTIVITIES

COMPUTER SCIENCE COLLOQUIUM

                    - Thursday, September 8, 1988

Dr.  Hans-Peter  Kriegel,  University  of  Bremen, West
Germany,  will  speak on ``Spatial Access Methods based
on Dynamic Hashing''.

TIME:                3:30 PM

ROOM:              DC 1302

ABSTRACT

In   order  to  handle  spatial  data  efficiently,  as
required   in   computer   aided  design  and  geo-data
applications,  a  database  management  system needs an
access  method  that  will  help it retrieve data items
quickly  according  to their spatial location.  We will
present  a  classification  of  existing spatial access
methods  and  show  that  they use one of the following
three  techniques:  clipping,  overlapping regions, and
transformation.   From  a  practical  point  of view we
provide  a  tool  box  supporting  simple  design  of a
spatial  access  method for a given point access method
using  one  of  the  above  techniques.  We analyze the
technique  of  transformation  in  more detail and show
that  our  new concept of asymmetric and non-orthogonal
partitioning  is  more  retrieval  efficient  than  the
traditional symmetric and orthogonal approach.