Database Security

Databases may be compromised by asking a set of queries which return only statistical information and making inferences about a specific entry from the results of the set of queries. We present methods of constructing the set of queries to compromise a database where all the queries in the set return the maximum of a set of k elements, or all queries return the mean of a set of k elements. In the case of the mean query, all elements involved will be compromised. We also consider bounds on the number of queries required to compromise the database.