  The problem of data exchange involves a source schema, a target schema and a
set of mappings from transforming the data between the two schemas. We study
the problem of data exchange in the presence of privacy restrictions on the
source. The privacy restrictions are expressed as a set of policy views
representing the information that is safe to expose over all instances of the
source. We propose a protocol that provides formal privacy guarantees and is
data-independent, i.e., if certain criteria are met, then the protocol
guarantees that the mappings leak no sensitive information independently of the
data that lies in the source. We also propose an algorithm for repairing an
input mapping w.r.t. a set of policy views, in cases where the input mapping
leaks sensitive information. The empirical evaluation of our work shows that
the proposed algorithm is quite efficient, repairing sets of 300 s-t tgds in an
average time of 5s on a commodity machine. To the best of our knowledge, our
work is the first one that studies the problems of exchanging data and
repairing mappings under such privacy restrictions. Furthermore, our work is
the first to provide practical algorithms for a logical privacy-preservation
paradigm, described as an open research challenge in previous work on this
area.
