Unification of Temporal Data Models

To add time su port to the relational model, both first normal form (fNF and non-INF appmches have maining within 1NF when time support is added may introduce data redundancy. The non-1NF models may not be capable of directly using existing relational storage structures or query evaluation stmtegies. This paper describes a new, conceptual tempoml data model that better captures the time-dependent semantics of the data while permitting multiple data models at the representation level. This conceptual model effectively moves the distinction between the various existing data models from a semantic basis to a physical, performance-relevant basis. We define a conceptual notion of a bitempoml relation where tuples are stamped with sets of twodimensional chronons in transaction-time/valid-time space. We introduce a tuple-timestamped 1NF representation to exemplify how the conceptual bitempoml data model is related, by means of snapshot equivalence, with representational models. We then consi...

• Type: Conference
• Year: 1993
• Where: ICDE
• Authors: Christian S. Jensen, Michael D. Soo, Richard T. Snodgrass
• Keywords: Conceptual, Data Model, Database, ICDE 1993, Representational Model