Temporal entity-relationship models-a survey

Abstract

The Entity-Relationship (ER) model, using varying notations and with some semantic variations, is enjoying a remarkable, and increasing, popularity in both the research community£the computer science curriculum£and in industry. In step with the increasing diffusion of relational platforms, ER modeling is growing in popularity. It has been widely recognized that temporal aspects of database schemas are prevalent and difficult to model using the ER model. As a result, how to enable the ER model to properly capture time-varying information has, for a decade and a half, been an active area in the database-research community. This has led to the proposal of close to a dozen temporally enhanced ER models. This paper surveys all temporally enhanced ER models known to the authors. It is the first paper to provide a comprehensive overview of temporal ER modeling and it, thus, meets a need for consolidating and providing easy access to the research in temporal ER modeling. In the presentation of each model, the paper examines how the time-varying information is captured in the model and presents the new concepts and modeling constructs of the model. A total of 19 different design properties for temporally enhanced ER models are defined, and each model is characterized according the these properties. Index Terms-Conceptual modeling, Entity-Relationship models, database design, temporal databases, temporal data models, design criteria for temporal ER models, time semantics.

Modelling Context Information with ORM

“…Although solutions exist for some of the problems discussed in the previous section (for example, for modelling temporal data [5] and information quality [6]), there is no single modelling approach that addresses all of the problems in a cohesive way. In this section, we outline a set of extensions to ORM that we developed to address most of the problems.…”

Modeling Concept Evolution: A Historical Perspective

“…In contrast, [19] and [8] maintain a single temporal document from which versions of any document fragment (even single elements) can be extracted directly when needed. A survey on temporal extensions to the Entity-Relationship (ER) model is presented in [6]. Change Management in Ontologies: There is a fundamental distinction between an actual update and a revision in knowledge bases [20].…”

“…These range from data manipulation languages, and maintenance of views under changes [2], to schema evolution [3] and mapping adaptation [4]. To cope with the history of data changes, temporal models have been proposed for the relational [5] and ER [6] models, for semi-structured data [7], XML [8] and for RDF [9]. Almost in its entirety, existing work on data changes is based on a data-oriented point of view.…”

Complexity of Reasoning over Temporal Data Models

“…Temporal conceptual data models [25,24,14,15,19,4,23,12] extend standard conceptual schemas with means to visually represent temporal constraints imposed on temporal database instances. According to the glossary [18], such constraints can be divided into three categories, to illustrate which we use the temporal data model in Fig.…”