  Consistent query answering over a database that violates primary key
constraints is a classical hard problem in database research that has been
traditionally dealt with logic programming. However, the applicability of
existing logic-based solutions is restricted to data sets of moderate size.
This paper presents a novel decomposition and pruning strategy that reduces, in
polynomial time, the problem of computing the consistent answer to a
conjunctive query over a database subject to primary key constraints to a
collection of smaller problems of the same sort that can be solved
independently. The new strategy is naturally modeled and implemented using
Answer Set Programming (ASP). An experiment run on benchmarks from the database
world prove the effectiveness and efficiency of our ASP-based approach also on
large data sets. To appear in Theory and Practice of Logic Programming (TPLP),
Proceedings of ICLP 2015.
