Database Design III : General Constraints
This chapter proposes a general framework for dealing with temporal database design questions. To be specific, it describes a set of requirements that apply to the design of the running example and (it’s claimed) can be used as a template for pinning down the requirements that apply to any temporal database. The chapter then shows how those requirements can be expressed in terms of formal integrity constraints for (a) a database consisting of current relvars only, (b) a database consisting of historical relvars only, and (c) a database consisting of a mixture of current and historical relvars. The chapter also offers some hope for automating the definitions of such constraints.