A data processing system in which a sequence of records, each record containing data items of various types, is processed. The system is operable in a "remember" mode in which, if a data item of a particular type is not present in a particular record, the result of the last time that type of data item...http://www.google.com/patents/US4064489?utm_source=gb-gplus-sharePatent US4064489 - Apparatus for searching compressed data file
