[dzidol]

There's such thing, at least in prototype stage. Like cryptDB, which, afaik is homomorphic with a nice property of preserving the order of encrypted keys. It leaks some information, but you can apply predicates different than equality, like `where a between 100 and 200`. In that case, the query passed to server will look like `where a between encrypted(100) and encrypted(200)` and server will be able to apply it, without knowing real values of the range limits or data stored in `a` column. With encryption function which don't preserve order, the data would need to be filtered client-side, so whole projection would be dumped to client and it would be the client who first decrypts the data, and then filters-out unnecessary rows.