SILVA, S. L. F.; http://lattes.cnpq.br/8698404338363397; SILVA, Sônia Leila Fernandes.
Resumen:
Recent database applications are typically oriented towards a large set of non-expert
users, and therefore, they need to be equipped with suitable interfaces facilitating the
interaction with the system. Moreover, the incorporation of time in database systems
is a desirable feature. Indeed, severals temporal data models and the corresponding
textual query languages have been proposed. However, there is a limited amount of
research concerning the investigation of user-oriented languages for querying temporal
databases. Our proposal addresses such a need. In particular, we propose a visual
query environment, namely TVQE (Temporal Visual Query Environment), which provides
an easier interaction of the user with temporal databases. The system adopts a
diagrammatic representation of the database schema (including temporal classes and
relationships) and a "graphical notebook" as interaction metaphor. In our approach,
non-database experts are released from syntactical difficulties which are typical of textual
languages, and they can easily express temporal queries by means of elementary
graphical operations (e.g. click on a node label). Differently from many proposals in the
field of visual query languages, the language underlying TVQE is provided w i t h formal
syntax and semantics. It is based on a minimal set of temporal graphical primitives
(TGPs), which are defined on a Temporal Graph Model (TGM), with visual syntax and
object-based semantics. We mainly concentrate on the formal aspects of TVQE, and
provide some ideas on the visual interaction mechanisms and implementation issues.