Temporal aspects of logical procedure definition

摘要

This paper discusses the inclusion of time in a message-oriented relational model of information systems in order to achieve memory independent specifications. The concept of memory independence is reviewed and several systems languages are analysed from this point of view and also in other aspects of their temporal properties. The concept of temporal database is formally introduced and a special modal tense logic is developed to deal with it. This logic is extended with a transition imperative logic to allow the specification of processes within the information system at a very high level. The information system is seen as composed of theses concurrent autonomous processes that communicate through the temporal database divided in event and state assertions.