An Extended Relational Database Model for Uncertain and Imprecise Information

We propose an extended relational database model which can model both uncertainty and imprecision in data. This model is basedon Dempster-Shafertheory which has become popular in AI as an uncertainty reasoningtool. The definitions of Be1 andPls functions in Dempster-Shafertheory are extended to compute the beliefs of various comparisons(e.g., equality, less than, etc.) between two basic probability assignments. Based on thesenew definitions of Be1 andPls functions and the Boolean combinations of Be1 and Pls values for two events,five relational operatorssuchasSelect,Cartesian Product, Join, Projection Intersect, and Union are defined. Keywords.. database systems, uncertainty, DempsterShafer theory, Artificial Intelligence, relational algebra, uncertain and imprecise information.

• Type: Conference
• Year: 1992
• Where: VLDB
• Authors: Suk Kyoon Lee
• Keywords: AndPls Functions, Database, Extended Relational Database, Uncertainty Reasoningtool, VLDB 1992