Classic Data Models

Abstract

In this chapter we discuss the two so-called classic data models: the hierarchical data model and the network data model. In section 1.5.3 we defined the idea of a classic data model in terms of record-orientation. In this sense, we might include the relational data model in amongst the classic data models. Here, the network and hierarchical data models are also described as being classic in the sense that they formed the basis for the first commercially available DBMS. Although currently relational systems have tended to outstrip network or hierarchical DBMS, a large number of legacy systems still exist running under these approaches.