Data sharing and exchange: General data-mapping semantics

Abstract

Traditional data sharing and exchange solved the problem of exchanging data between applications that store same information using different vocabularies. We discuss in this paper the data sharing and exchange problem between applications that store related data which do not necessarily possess the same meaning. We first consider this problem in settings where source instances are complete – that is, do not contain unknown data. Then we address more collaborative scenarios where peers can store incomplete information. We define the semantics of these settings, and we provide the data complexity for generating solutions and the minimal among those. Also, we distinguish between sound and complete certain answers as semantics for conjunctive query answering.