Approximate Data Exchange

Abstract. We introduce approximate data exchange, by relaxing classical data exchange problems such as Consistency and Typechecking to their approximate versions based on Property Testing. It provides a natural framework for consistency and safety questions, which first considers approximate solutions and then exact solutions obtained with a Corrector. We consider a model based on transducers of words and trees, and study -Consistency, i.e., the problem of deciding whether a given source instance I is -close to a source I , whose image by a transducer is also -close to a target schema. We prove that -Consistency has an -tester, i.e. can be solved by looking at a constant fraction of the input I. We also show that -Typechecking on words can be solved in polynomial time, whereas the exact problem is PSPACE-complete. Moreover, data exchange settings can be composed when they are close.

• Type: Conference
• Year: 2007
• Where: ICDT
• Authors: Michel de Rougemont, Adrien Vieilleribière
• Keywords: Approximate Data Exchange, Data Exchange, Data Exchange Problems, Database, ICDT 2007