Abstract:
Fact-based models are built by expressing elementary facts using natural verbalizations. By generalizing individual objects to object types, facts to fact types, and adding constraints, a schema for any domain can be constructed.
Fact-based schemas have many advantages, including being highly amenable to construction of natural verbalizations, since they were originally derived from such verbalizations. However, it is not common practice to consider queries during modeling, so only limited attention has been paid to how to model them. Queries are not only useful for extracting data, but also to express complex business constraints.
This paper presents an effective meta-model for fact-based queries as an extension of a tiny subset of the meta-model of Object Role Modeling. Examples expressed in the Constellation Query Language show how to populate the query meta-model.
Author:
Clifford Heath
Data Constellation
Australia