1. A computer-implemented method for staging data record changes from a faster storage medium to a slower storage medium using data query rewriting, the computer-implemented method comprising: responsive to a computer receiving a data query corresponding to a particular data record, determining, by the computer, whether the data query is one of a transactional data query or an analytical data query; responsive to the computer determining that the data query is a transactional data query, rewriting, by the computer, the transactional data query to apply transactional delta changes to the particular data record on a storage-class memory of the computer; and responsive to the computer determining that the data query is an analytical data query, rewriting, by the computer, the analytical data query to select and reconcile each data record corresponding to the particular data record stored on the storage-class memory with the particular data record stored on a persistent data storage device of the computer.