an architecture for high-level language database extensions
This paper describes an architecture for a set of database extensions to the existing high-level languages. The scheme described forms an architecture in the sense that it is not based on any particular language: its constructs and functions, or some suitable subset of them, may be mapped into the concrete syntax of a number of distinct languages, among them COBOL and PL/I. The architecture includes both the means for specifying the programmer's view of a database (i.e. for defining the external schema) and the means for manipulating that view. A significant feature is that the programmer is provided with the ability to handle all three of the well-known database structures (relational, hierarchical, network), in a single integrated set of language extensions. Another important aspect is that both record- and set-level operations are provided, again in an integrated fashion. The objectives of the architecture are to show that it is possible for relational, hierarchical and network support to co-exist within a single language, and also, by providing a common framework and treating the three structures in a uniform manner, to shed some new light on the continuing debate on the relative merits of each.The paper is intended as an informal introduction to the architecture, and to this end includes several illustrative examples which make use of a PL/I-based concrete syntax.
architecture language database extensibility paper scheme programmer schema feature relation hierarchic network integrability language extensibility aspect operability object support lighting informal examples use  framework 