Doi: 10.1145/1400181.1400195
How do we apply the concept of resource
orientation by designing representations
to support interactions?
By eRik wiLDe anD RoBeRt J. GLushko
Document
Design
matters
THE CLASSICAL APPROACH to the data aspect of system
design distinguishes conceptual, logical, and physical
models. Models of each type or level are governed by
metamodels that specify the kinds of concepts and
constraints that can be used by each model; in most
cases metamodels are accompanied by languages for
describing models. For example, in database design, conceptual models usually conform to the Entity-Relationship
(ER) metamodel (or some extension of
it), the logical model maps ER models to relational tables and introduces
normalization, and the physical model
handles implementation issues such
as possible denormalizations in the
context of a particular database schema language. In this modeling methodology, there is a single hierarchy of
models that rests on the assumption
that one data model spans all modeling levels and applies to all the applications in some domain.a
a This simplified view may change if different
implementations of the same conceptual
model use different lower-level models, per-
The “one true model” approach assumes homogeneity, but that does not
work very well for the Web. The Web
as a constantly growing ecosystem of
heterogeneous data and services has
challenged a number of practices and
theories about the design of IT landscapes. Instead of being governed by
“one true model” used by everyone,
the underlying assumption of top-down design, Web data and services
evolve in an uncoordinated fashion. As
a result, a fundamental challenge with
Web data and services is matching and
haps for performance optimization reasons.
In this case, the lower-level models are derived
from the conceptual model, but they are also
based on different assumptions about access
patterns and required performance.
