[GRSa98] The DEDALE System for Complex Spatial Queries
Conférence Internationale avec comité de lecture :
ACM-SIGMOD Intl. Conf. on the Management of Data (SIGMOD'98),
January 1998,
motcle:
Résumé:
This paper presents DEDALE, a spatial database system intended to
overcome some limitations of current systems by providing an
abstract and non-specialized data model and query language for the
representation and manipulation of spatial objects. \dedale/ relies
on a logical model based on linear constraints, which generalizes
the constraint database model of KKR90. While in the
classical constraint model, spatial data is always decomposed into
its convex components, in DEDALE holes are allowed to fit the need
of practical applications. The logical representation of spatial
data although slightly more costly in memory, has the advantage of
simplifying the algorithms. DEDALE relies on nested relations, in
which all sorts of data (thematic, spatial, etc.) are stored in a
uniform fashion. This new data model supports declarative query
languages, which allow an intuitive and efficient manipulation of
spatial objects. Their formal foundation constitutes a basis for
practical query optimization. We describe several evaluation rules
tailored for geometric data and give the specification of an
optimizer module for spatial queries. Except for the latter module,
the system has been fully implemented upon the O$_2$ DBMS, thus
proving the effectiveness of a constraint-based approach for the
design of spatial database systems.