Digitally encoded data such as classified advertising and other data bases of similarly related messages are broadcast on a serial-type digital data transmission system. Each message is preceded by a headnote, structured so that upon reception, the receiver can select messages based upon a combination of hierarchical and relational views of the message data, without any interaction whatsoever with the broadcast system. "Hierarchical access" means that messages are considered in categories and sub-categories. "Relational access" means that within sub-categories access is possible by a combination of attributes or keywords (i.e. using "and", "or", and "not" to combine multiple key phrases). We call the invention ReQueSt-DB. The name is derived from "Relational Queries on Sequential Data Bases". ReQueSt-DB allows rapid and facile access to one-way, cyclically broadcast, bit serial, sequential data bases consisting of (possibly) many thousands of messages with high selectivity. In the content of a particular broadcast data base (i.e. one in which part of the data base is classified advertising), a ReQueSt-DB query might be the logical equivalent of "Show me on my television screen the set of classified, real estate ads which describe houses for sale in the Lehigh Valley, Pennsylvania, which are in either Allentown or Bethlehem but not in Easton, and that have 3 or more bedrooms and have central air conditioning and may or may not have a family room and are priced between $60, 000 and $100, 000".