Algebraic Graph - Oriented = Category - Theory - BasedManifesto

Foreword. Category theory is well known as a high-level polymorphic framework suitable for specifying complex structures and formalisms. Quite unexpectedly, however, it turned out that even elementary category theory notions can be valuable in practice of software engineering (see JD93, DDJ93, CD95, CD96]), and in the summer of 1994 we wrote a manifesto ((CD94], the rst version of the present one a) to claim our belief in the extreme fruitfulness of incorporating the category theory (CT) machinery into the database (DB) area. That time we did not know about works by Johnson with coauthors (see JD93] for references) which seem to be the rst publications on the real innuence of CT machinery in the DB eld. So, a real mutual liking between CT and DB is about three years old. We cannot say that their relations were unclouded during these years, and now we recognize quite clearly that theoretical achievments do not directly lead to revolutions in the eld of information (and any other) technologies: the normal way of changes in the latter is the way of more or less rapid evolution which is more or less modulated by theoretical ideas. Nevertheless, we consider the last two years as a connrmation of our previous predictions: the list of (CT+DB)-publications is actually growing (though not so rapidly as we hoped), and at a recent International Workshop ((BKZ95]) there was a special section on (CT+DB), and it seems that methodologies being developed in Sydney ((JD93, DDJ93]) and Riga ((CD95, CD96]) meet some (methodological, of course, but partly also technological) challenges in the DB area. As before, we forecast an intensive growth of CT and DB interaction and present below the third version of our manifesto in which the text is slightly revised and the bibliography list is updated. a Boris Cadish of that paper and Boris Kadish of the present one are the same person 1 Foreword to the rst version. Nowadays is the time when the distance between a computer science research and its practical application is dramatically decreasing. Moreover, now we live in such an informationized world that even the distance between a declaration of an idea and its advanced elaboration is also decreasing. That is why it is the time of sci-entiic declarations often called manifestos as, for instance, "The Object-Oriented Database System Manifesto" by M. Atkinson et al ((ABD + 89]), "Third-Generation Data Base System Manifesto" by M. …