ENTITY/EVENT DATA MODELLING METHOD.

Abstract

To date, system and data modelling techniques have concentrated almost exclusively on static views of the systems being modelled. What is modelled is a time slice of a given system's existence. The system dynamics are only modelled implicity and obscurely in the transaction consistency rules. The explicit modelling of the system dynamics - the system behavior - has only been attempted hitherto in simulation languages. A pioneering attempt by M. A. Jackson to show how dynamic system models such as could be defined in, say, SIMULA 67, can be programmed in COBOL has not received a great deal of attention. This is because it has only been applied to simple systems with a single entity type and no parallelism. This paper shows how the technique can be applied in more realistic cases.