News

Student tutors for the course Data Modelling wanted (winter term 2021/22)


IT-Project Data Souvereignty in winter termin 2021/22


Business Intelligence: Washing Gold in Times of Information Overload


See all news.


Campusplan

campusplan_image

You can find us here.




Defining Web Schema Transformers by Example

Authors: S. Lechner, M. Schrefl
Paper: Lech03a (2003)
Citation: Valdimír Marík, Werner Retschitzegger, Olga Stepánková (eds.): Proceedings of the 14th International Conference on Database and Expert Systems Applications (DEXA 2003), Prague, Czech Republic, September 2003, Springer Verlag, pp. 46-56, 2003.
Resources: Copy  (In order to obtain the copy please send an email with subject  Lech03a  to dke.win@jku.at)


Abstract:

When defining a scheme of a web application (a web scheme) using a conceptual modelling tool, modelers successively perform design steps by extending or refining the scheme. Each design step is characterized by (i) the scheme to which the design step is applied (input scheme) and (ii) the resulting scheme (output scheme). As modelers apply similar design steps repeatedly, it would be convenient to have schema transformers that, when applied to an input scheme, generate an output scheme.

In this paper, we present a way of defining schema transformers by example. A transformer comprises an input and an output template that are parameterized examples of an input and an output scheme, respectively. Therefrom executable code necessary for performing transformations can be generated automatically. A transformer is applied to an input scheme by binding elements of the scheme to parameters. For each such application, a corresponding output scheme is then generated.

Our transformers can be introduced in various models/tools for web application modelling. We demonstrate this on the example of WebML.

Keywords:schema transformers, query by example, conceptual web application modelling