A method and system for sorting data of an input file containing multiple records associated with multiple tables of a database. The multiple records include key values. The key values are segmented into ranges of key values for each table. Each range of key values for each table is a segment having a segment value. A block number, which contains a unique permutation of the segment values of the segments, is generated. The segment values denote the ranges of key values encompassing multiple key values in each record. A sort key value for each record is ascertained, based on the generated block number for each record, and added to each record. The multiple records are sorted according to the sort key values in the multiple records. The sorted multiple records are stored in an output file. The selected multiple key values include all key values that satisfy a condition.