Extended SQL support for uncertain data

Abstract

Although the relational model for databases provides a great range of advantages over other data models, it lacks a comprehensive way for handling uncertain data. Uncertainty in data values, however, is pervasive in all real world environments and has received some attention in the literature. Several methods have been proposed for incorporating uncertain data into relational databases; however, these approaches have many shortcomings. In this paper, we discuss a probabilistic extension of the relational model and propose a query language for creation, modification, and retrieval of uncertain data.