US Patent 10489348 Performing hash joins using parallel processing

Data records are joined using a computer. Data records in a first plurality of data records and a second plurality of data records are hashed. The data records in the first and second pluralities are respectively assigned to first and second groupings based on the hashes. Associated pairs of groupings from the first and second groupings are provided to a thread executing on a computer processor, and different pairs are provided to different threads. The threads operate on the pairs of groupings in parallel to determine whether to join the records in the groupings. A thread joins two data records under consideration if the hashes associated with the data records match. The joined data records are output.