UNIVERSITY OF HELSINKI -
DEPARTMENT OF COMPUTER SCIENCE
VIERAILULENTO
Prof. Emmanuel Waller (LRI, Universite de Paris-Sud, Centre d'Orsay)
pitää torstaina 5.9.1996 klo 14-16 Tietojenkäsittelytieteen laitoksen
salissa A414 vierailuluennon aiheest
On Object Migration in Object-Oriented Databases:
Some Issues, Solutions, and Applications
Abstract
We study a mechanism that supports the migration of objects from
one class of an OODB to another, thereby enabling us to model the same
object playing different roles throughout its lifetime.
Object migration may introduce typing conflicts
due to the different typing constraints imposed by the classes.
We present a coercion-like adaptation process that automatically resolves
these conflicts.
The process combines re-classification of objects and modification of
attributes. We study the computational complexity of the problem,
and show that the adaptation process can be performed efficiently in
databases with covariant schemas
(This work is in: A. Mendelzon, T. Milo, E. Waller: Object Migration,
PODS'94)
Tervetuloa.
Gösta Grahne