Database Queries and Constraints via Lifting Problems

Oct 11, 2013 | Technical Papers

Abstract We interpret SPARQL graph patterns as category-theoretic lifting problems. Each query is a lift in a certain category, and the set of solutions to the query corresponds to the set of lifts. We describe how giving users access to certain parts of this...

Allegories for Database Modeling

Jan 21, 2013 | Resources

Abstract Allegories are categories modeled upon the category of sets and binary relations (where sets are objects and binary relations are morphisms composed using joins). In this paper we present a new conceptual data modeling formalism based on the language of...

Functorial Data Migration

Aug 18, 2012 | Technical Papers

Abstract We present a simple database definition language of categories and functors. A database schema is a small category, and an instance is a set-valued functor on it. We show how morphisms of schemas induce three data migration functors which parameterize...