An architecture for supporting interoperability among temporal databases

A significant property of temporal data is their richness of semantics. Although several temporal data models and query languages have been designed specifically to handle the temporal data, users must still deal with much of the implicit temporal information, which can be automatically derived from the stored data in certain situations. We propose a multidatabase architecture where an appropriate formalization of the intended semantics is associated with each temporal relation and temporal database. This allows a temporal mediator to access the databases to retrieve implicit information in terms of time granularities different from those used to store data. We also describe how the temporal mediator can provide a user interface to the multidatabase system allowing temporal queries in terms of arbitrary granularities and involving relations in different TDBMS.