  This paper revisits the problem of repairing and querying inconsistent
databases equipped with universal constraints. We adopt symmetric difference
repairs, in which both deletions and additions of facts can be used to restore
consistency, and suppose that preferred repair actions are specified via a
binary priority relation over (negated) facts. Our first contribution is to
show how existing notions of optimal repairs, defined for simpler denial
constraints and repairs solely based on fact deletion, can be suitably extended
to our richer setting. We next study the computational properties of the
resulting repair notions, in particular, the data complexity of repair checking
and inconsistency-tolerant query answering. Finally, we clarify the
relationship between optimal repairs of prioritized databases and repair
notions introduced in the framework of active integrity constraints. In
particular, we show that Pareto-optimal repairs in our setting correspond to
founded, grounded and justified repairs w.r.t. the active integrity constraints
obtained by translating the prioritized database. Our study also yields useful
insights into the behavior of active integrity constraints.
