Disjunctive datalog

T Eiter, G Gottlob, H Mannila - ACM Transactions on Database Systems …, 1997‏ - dl.acm.org
We consider disjunctive Datalog, a powerful database query language based on disjunctive
logic programming. Briefly, disjunctive Datalog is a variant of Datalog where disjunctions …

Elements of relational database theory

PC Kanellakis - Formal models and semantics, 1990‏ - Elsevier
Publisher Summary This chapter presents a systematic and unifying introduction to
relational database theory, including some of the recent developments in database logic …

Datalog extensions for database queries and updates

S Abiteboul, V Vianu - Journal of Computer and System Sciences, 1991‏ - Elsevier
Deterministic and non-deterministic extensions of Datalog with fixpoint semantics are
proposed, and their expressive power characterized. It is argued that fixpoint semantics …

Naturally embedded query languages

V Breazu-Tannen, P Buneman, L Wong - Database Theory—ICDT'92: 4th …, 1992‏ - Springer
We investigate the properties of a simple programming language whose main computational
engine is structural recursion on sets. We describe a progression of sublanguages in this …

Dyn-FO (preliminary version): a parallel, dynamic complexity class

S Patnaik, N Immerman - Proceedings of the thirteenth ACM SIGACT …, 1994‏ - dl.acm.org
Traditionally, computational complexity has considered only static problems. Classical
Complexity Classes such as NC, P, NP, and PSPACE are defined in terms of the complexity …

Towards tractable algebras for bags

S Grumbach, T Milo - Proceedings of the twelfth ACM SIGACT-SIGMOD …, 1993‏ - dl.acm.org
Bags, ie sets with duplicates, are often used to implement relations in database systems. In
this paper we study the expressive power of algebras for manipulating bags. The algebra we …

Normal forms and conservative properties for query languages over collection types

L Wong - Proceedings of the twelfth ACM SIGACT-SIGMOD …, 1993‏ - dl.acm.org
Strong normalization results are obtained for a general language for collection types. An
induced normal form for sets and bags is then used to show that the class of functions whose …

Structural recursion as a query language

P Buneman, V Tannen, S Naqvi - Proceedings of 3rd …, 1991‏ - research.ed.ac.uk
We propose a programming paradigm that tries to get close to both the semantic simplicity of
relational algebra, and the expressive power of unrestricted programming languages. Its …

The power of languages for the manipulation of complex values

S Abiteboul, C Beeri - The VLDB Journal, 1995‏ - Springer
Various models and languages for describing and manipulating hierarchically structured
data have been proposed. Algebraic, calculus-based, and logic-programming oriented …

A graph-based data model and its ramifications

M Levene, G Loizou - IEEE Transactions on Knowledge and …, 1995‏ - ieeexplore.ieee.org
Currently, database researchers are investigating new data models in order to remedy the
deficiencies of the flat relational model when applied to nonbusiness applications. Herein …