1. A data processing system comprising: a bus system; a communications system connected to the bus system; a memory connected to the bus system, wherein the memory includes a set of instructions; and a processing unit connected to the bus system, wherein the processing unit executes the set of instructions to compute a plurality of hash functions of data values in a data item; determine a corresponding memory location for one of the plurality of hash functions of data values in the data item; store the data item in the memory location, wherein each memory location stores a plurality of stored data items; store a key portion of all data items contiguously within the memory location; and store a payload portion of all data items contiguously within the memory location.