Abstract
Previous work has addressed the issues of idempotence and boundedness for various restricted classes of Horn-clause queries. In this paper, we consider queries consisting of a single clause containing a single predicate symbol. As such, these queries are a notational variant of the full, untagged tableau queries with recursive semantics. The study of the idempotence and boundedness for single-clause, single-predicate queries has previously been restricted to the typed case. We generalize these results to obtain syntactic, polynomial-time computable characterizations of idempotence for certain classes of untyped queries.
This research was supported by the Natural Sciences and Engineering Research Council of Canada.
This is a preview of subscription content, log in via an institution to check access.
Preview
Unable to display preview. Download preview PDF.
References
A.V. Aho, Y. Sagiv, and J.D. Ullman, “Equivalences among Relational Expressions,” SIAM J. Comput., vol. 8, no. 2, pp. 218–246, 1979.
A.V. Aho and J.D. Ullman, “Universality of Data Retrieval Languages,” Proc. 6th ACM Symp. on Principles of Programming Languages, pp. 110–120, 1979.
F. Bancilhon and R. Ramakrishnan, “An Amateur's Introduction to Recursive Query Processing Strategies,” Proc. ACM SIGMOD Conf. on Management of Data, pp. 16–52, 1986.
C. Beeri and M.Y. Vardi, “Formal Systems for Tuple and Equality Generating Dependencies,” SIAM J. Comput., vol. 13, no. 1, pp. 76–98, 1984.
A.K. Chandra and P.M. Merlin, “Optimal Implementation of Conjunctive Queries in Relational Data Bases,” Proc. 9th ACM Symp. on Theory of Computing, pp. 77–90, 1977.
E. F. Codd, “Relational Completeness of Data Base Sublanguages,” in Data Base Systems, ed. R. Rustin, pp. 65–98, Prentice-Hall, Englewood Cliffs, N. J, 1972.
S. Cosmadakis and P. Kanellakis, “Parallel Evaluation of Recursive Rule Queries,” Proc. 5th ACM SIGACT—SIGMOD Symp. on Principles of Database Systems, pp. 280–293, 1986.
I.F. Cruz, A.O. Mendelzon, and P.T. Wood, “A Graphical Query Language Supporting Recursion,” Proc. ACM SIGMOD Conf. on Management of Data, pp. 323–330, 1987.
Y.E. Ioannidis, “A Time Bound on the Materialization of Some Recursively Defined Views,” Proc. 11th Int. Conf. on Very Large Data Bases, pp. 219–226, 1985.
J. Naughton, “Data Independent Recursion in Deductive Databases,” Proc. 5th ACM SIGACT—SIGMOD Symp. on Principles of Database Systems, pp. 267–279, 1986.
J. Naughton and Y. Sagiv, “A Decidable Class of Bounded Recursions,” Proc. 6th ACM SIGACT-SIGMOD-SIGART Symp. on Principles of Database Systems, pp. 227–236, 1987.
Y. Sagiv, “On Computing Restricted Projections of Representative Instances,” Proc. 4th ACM SIGACT—SIGMOD Symp. on Principles of Database Systems, pp. 171–180, 1985.
Y. Sagiv, “On Bounded Database Schemes and Bounded Horn-Clause Programs,” SIAM J. Comput., vol. 17, no. 1, pp. 1–22, 1988.
Y. Sagiv and M. Yannakakis, “Equivalence among Relational Expressions with the Union and Difference Operators,” J. ACM, vol. 27, no. 4, pp. 633–655, 1980.
J.D. Ullman, Principles of Database Systems, Computer Science Press, Potomac, Md., 1983.
Author information
Authors and Affiliations
Editor information
Rights and permissions
Copyright information
© 1988 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Wood, P.T., Mendelzon, A.O., Atzeni, P. (1988). Idempotent single-predicate horn clauses. In: Gyssens, M., Paredaens, J., Van Gucht, D. (eds) ICDT '88. ICDT 1988. Lecture Notes in Computer Science, vol 326. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-50171-1_8
Download citation
DOI: https://doi.org/10.1007/3-540-50171-1_8
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-50171-8
Online ISBN: 978-3-540-45943-9
eBook Packages: Springer Book Archive