DATABASE MODELS FOR INFINITE AND INDEFINITE TEMPORAL INFORMATION

Representation and querying of temporal information can benefit from the integration of techniques from constraint databases, database models for indefinite information and reasoning about temporal constraints. With this perspective in mind, we present a hierarchy of temporal data models: temporal relations, generalized temporal relations and temporal tables. We study the semantics of these models and develop algebraic and calculus query languages for them. The proposed models can be useful to several novel applications include planning, scheduling, project management, medical information systems, geographical information systems and natural language processing systems.