Language-integrated Provenance in Links

Today’s programming languages provide no support for data provenance. In a world that increasingly relies on data, we need provenance to judge the reliability of data and therefore should aim for making it easily accessible to programmers. We report our work in progress on an extension to the Links programming language that builds on its support for language-integrated query to support where-provenance queries through query rewriting and a type system extension that distinguishes provenance metadata from other data. Our approach aims to work solely within the language implementation and thus require no changes to the database system. The type system together with automatic propagation of provenance metadata will prevent programmers from accidentally changing provenance, losing it, or misattributing it to other data.