Temporal E-R Modelling with description logics
نویسندگان
چکیده
Recent e orts in the Conceptual Modelling community have been devoted to properly capturing time-varying information. Various temporally enhanced Entity-Relationship (ER) models have been proposed that are intended to model the temporal aspects of database conceptual schemas. This work gives a logical formalisation of the various properties that characterise and extend di erent temporal ER models which are found in literature. The formalisation we propose is based on Description Logics (DL), which have been proved useful for a logical reconstruction of the most popular conceptual data modelling formalisms. The proposed DL has the ability to express both enhanced temporal ER schemas and integrity constraints in the form of complex inclusion dependencies. Reasoning in the devised logic is decidable, thus allowing for automated deductions over the whole conceptual representation, which includes both the ER schema and the integrity constraints over it.
منابع مشابه
Temporal ER Modelling with Description Logics: A Preliminary Report
Recent efforts in the Conceptual Modelling community have been devoted to properly capturing time-varying information. Various temporally enhanced Entity-Relationship (ER) models have been proposed that are intended to model the temporal aspects of database conceptual schemas. This work gives a logical formalisation of the various properties that characterise and extend different temporal ER mo...
متن کاملA A Cookbook for Temporal Conceptual Data Modelling with Description Logics
We design temporal description logics suitable for reasoning about temporal conceptual data models and investigate their computational complexity. Our formalisms are based on DL-Lite logics with three types of concept inclusions (ranging from atomic concept inclusions and disjointness to the full Booleans), as well as cardinality constraints and role inclusions. The logics are interpreted over ...
متن کاملTemporal Conceptual Modelling with DL-Lite
Conceptual modelling formalisms such as the Entity-Relationship model (ER) and Unified Modelling Language (UML) have become a de facto standard in database design by providing visual means to describe application domains in a declarative and reusable way. On the other hand, both ER and UML turned out to be closely connected with description logics that are underpinned by formal semantics and th...
متن کاملE-connections of Description Logics
1 Motivation Combining description logics (DLs) with other logical formalisms, including other DLs, is an important and challenging task. Recent examples include: 1. the combination of DLs with temporal logics to form multi-dimensional temporal DLs, cf. e.g. [1, 6, 10]; 2. the fusion of multiple DLs into a single formalism that inherits decidability from its components, cf. [2]; 3. the combinat...
متن کاملTemporalising OWL 2 QL
We design a temporal description logic, TQL, that extends the standard ontology language OWL2QL, provides basic means for temporal conceptual modelling and ensures first-order rewritability of conjunctive queries for suitably defined data instances with validity time.
متن کامل