IMPLEMENTATION OF COMPLEX OBJECT SEMANTICS IN THE ANGEL SYSTEM

In order to satisfy the special demand of engineering applications, a next generation engineering data base management system （EDBMS）——ANGEL has been developed. The data model and features of ANGEL are introduced first. And then explained are how to express the semantics of the complex objects and how to model and manipulate them in the ANGEL system. Described in detail is the implementation of the ANGEL’s data manipulation language——ADML, which can support the semantics of the complex objects, especially the reference and inheritance relationship in complex nested table models.