A critique of the SQL database language

Abstract

The ANS Database Committee (X3H2) is currently at work on a proposed standard relational database language (RDL), and has adopted as a basis for that activity a definition of the "structured query language" SQL from IBM [10]. Moreover, numerous hardware and software vendors (in addition to IBM) have already released or at least announced products that are based to a greater or lesser extent on the SQL language as defined by IBM. There can thus be little doubt that the importance of that language will increase significantly over the next few years. Yet the SQL language is very far from perfect. The purpose of this paper is to present a critical analysis of the language's major shortcomings, in the hope that it may be possible to remedy some of the deficiencies before their influence becomes too all-pervasive. The paper's standpoint is primarily that of formal computer languages in general, rather than that of database languages specifically.