An O(n2) algorithm for fan-out free query optimization
An optimization algorithm for fan-out free queries, which form an untyped subclass of conjunctive queries, based on the implication graph technique is presented. The algorithm takes O(n2) steps where n is the size of the query. This algorithm subsumes all known algorithms for optimizing subclasses of fan-out free queries.
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- [ASU]A.V.Aho,Y.Sagiv and J.D.Ullman, Efficient optimization of a class of relational expressions, ACM Trans. on Database Systems, Vol. 4, No. 4, Dec 1979.Google Scholar
- [CM]A.K.Chandra and P.M.Merlin, Optimal implementation of conjunctive queries in relational databases, Proc. 9th Annual Symposium on Theory of Computation, May 1977.Google Scholar
- [DM]P.Dublish and S.N.Maheshwari, Optimization of a subclass of fan-out free queries, Unpublished Manuscript, Feb 1987.Google Scholar
- [JK]D.S.Johnson and A.Klug, Optimizing conjunctive queries that contain untyped variables, SIAM Journal on Computing, Vol. 12, No. 4, Nov 1983.Google Scholar
- [MM]B.N.S.Murthy and S.N.Maheshwari, Optimization of a class of relational expressions, Proc. 2nd Annual Conference on Foundations of Software Technology and Theoretical Computer Science, Bangalore, 1982.Google Scholar
- [MDM]B.N.S.Murthy, P.Dublish and S.N.Maheshwari, Some negative results on the optimization of conjunctive queries, Technical Report TR 85/01, Deptt. of Computer Science and Engg., IIT Delhi, Dec 1985.Google Scholar
- [Mai]D.Maier, The Theory of Relational Database, Computer Science Press, 1983.Google Scholar
- [Sag]Y.Sagiv, Quadratic algorithms for minimizing joins in restricted relational expressions, SIAM Journal on Computing, Vol. 12, No. 2, May 1983.Google Scholar
- [Ull]J.D.Ullman, Principles of Database Systems, Computer Science Press, 1982.Google Scholar