1. A data processing system, comprising: a relational database for storage of transaction data; an OLAP database for storage of a replication of the transaction data in an OLAP cube; means for storing data indicative of a replication time; a random access memory; means for receiving a data request, the data request specifying at least a first time interval; means for reading OLAP cube data from the OLAP cube; means for storing the OLAP cube data in the random access memory; means for determining the replication time using the data indicative of the replication time; means for generating a query for the relational database specifying a second time interval, the second time interval having a lower limit given by the replication time and an upper limit given by the upper limit of the first time interval; means for receiving replication data from the relational database in response to the query; means for storing the replication data in the random access memory; and means for generating an output using the OLAP cube data and the replication data stored in the random access memory.