A method comprises receiving, by a server computer, a request message comprising at least a credential from a client device. The server computer can hash the credential to form an altered value. The server computer can then determine whether or not the altered value matches one of the hashed values stored in the database. If the altered value matches a matched hashed value, the server computer can determine a range of a plurality of ranges. The range can be associated with the matched hashed value. The server computer can then determine a data item associated with the range. The server computer can provide the data item to the client device.