1. A method for proving the correctness of a query result produced by a data publisher while preserving data privacy, the method comprising: delivering a public key of a public key/private key pair from a data owner to a client; delivering data and cryptographic metadata to at least one data publisher, wherein the metadata is associated both with the data and the public key of the public key/private key pair; receiving a query from the client; returning a query result and a verification object from the data publisher to the client in response to the query; and verifying the correctness of the query result, wherein the correctness of the query result is verified utilizing the verification object and the public key.