SYSTEMATICS: its syntax and semantics as a query language (2)
Amı́lcar Sernadas · The Computer Journal · 1981
SYSTEMATICS (a very high level specification language) is shown to be incomplete as a data base query language. Some extensions are proposed in order to ensure the desired degree of relational completeness. Moreover, the set-oriented SYSTEMATICS is compared with a predicate-oriented query language in order to assess the practical interest of the main construct of SYSTEMATICS (the identification construct). A proof of the completeness of the extended version of SYSTEMATICS is outlined. A concrete syntax for this version is proposed. The semantics of this extended version is developed within a set theoretic framework.