Temporal Object Role Modelling

. We present a temporal object model capable of representing object lifespans and also the history of their roles and associations. We adopt an approach of temporal generalisation rather than temporal extension in which a model in its entirety is given a temporal semantics through an orthogonal generalisation of all model concepts -- including the lifespan of object roles themselves and constraints over these roles. The model is based on the generic object data model OM and its algebra has been generalised into a full temporal algebra over object roles. 1 Introduction Full support for temporal databases requires a complete generalisation of a data model with a temporal dimension. This means that all aspects of the model -- constructs, operations and constraints -- must have temporal generalisations. Further, the temporal dimension should apply not only to data, but also to metadata. Many existing proposals for temporal data models and systems -- both relational and object-oriented --..