
Accession Number : ADA141130
Title : A New Approach to Database Logic.
Descriptive Note : Technical rept.,
Corporate Author : STANFORD UNIV CA DEPT OF COMPUTER SCIENCE
Personal Author(s) : Kuper,G M ; Vardi,M Y
PDF Url : ADA141130
Report Date : Jan 1984
Pagination or Media Count : 11
Abstract : In this paper the authors propose a mathematical framework for unifying and generalizing the three principal data models, i.e., the relational, hierarchical and network models. Until recently most work on database theory has focussed on the relational model, mainly due to its elegance and mathematical simplicity compared to the other models. Some of this work has pointed out various disadvantages of the relational model, among them its lack of semantics and the fact that it forces the data to have a flat structure that the real data does not always have. In the model the authors propose here a database scheme is an arbitrary directed graph. As in the format model, leaves (i.e., nodes with no outgoing edges) represent data, and internal nodes have a function r on L, that assigns rvalues to these lvalues, and the authors require that the rvalues be of the correct form, depending on the type of the node.
Descriptors : *Mathematical models, *Data bases, *Computer logic, Graphs, Formats, Algebra, Semantics, Formulas(Mathematics), Interrogation, Data management
Subject Categories : Theoretical Mathematics
Distribution Statement : APPROVED FOR PUBLIC RELEASE