Several proposals for extending the relational data model to incorporate the
temporal dimension of data have appeared in the past several years. These
proposals have differed considerably in the way that the temporal dimension
has been incorporated both into the structure of the extended relations that
are defined as part of these extended model, and into the operations of the
extended relational algebra or calculus component of the models. Because
of these differences it has been difficult to compare the proposed models and
to make judgements as to which of them is "better" or indeed, the "best."
In this paper we propose a notion of historical relational completeness,
analogous to Codd's notion of relational completeness, and examine several
historical relational proposals in light of this standard.Information Systems Working Papers Serie
