DATABASE SEGMENT SEARCHING

A segment encompasses a number of segment records less than the total number of records of a database. The segment records have values for a field of the database. Lowest and highest values of the segment records for the field, and a bitmap for the segment, can be determined and stored. Selected bits of the bitmap each correspond to a value for the field. Each selected bit is set to one where at least one segment record has the value to which the bit corresponds. An index relating to just the segment records can be determined and stored. The lowest and highest values, and the bitmap, are adapted to permit determination of whether the segment has to be loaded into memory to locate records that satisfy a query. The index is adapted to permit searching of the segment records after the segment has been loaded into the memory.