System Models - 2
Widely used system models:
- Data-flow models:
- Show how data is processed by a system
- Data-flow models are basic system models of Structured Systems Analysis [DeMarco,1978]
- Semantic data models:
- Identify the data entities, their attributes, and relationships between them
- Examples: Entity-Relationship Modeling [Chen,1976] SDM [Hammer/McLeod,1981] RM/T (extension of the relational model) [Codd,1979]
- Object models:
- Represent data and its processing (together with structure of the data)
- Various notations: [Booch,1994] [Coad/Yourdon,1990] [Rumbaugh et al.,1991] [Coleman et al.,1994] [Fowler et al. 1997]