Embedding a relational data sublanguage in a general purpose programming language

Abstract

This paper describes EQUEL, a programming language which embeds the relational data sublanguage QUEL into the general purpose programming language “C”. Both QUEL and EQUEL are operational parts of the INGRES relational data base management system at Berkeley. Also briefly described are two operational subsystems written in this combined language. Lastly some of the language oriented shortcomings that have been observed in QUEL and EQUEL are discussed.