Counting-based normalization for multiple linear recursions
Normalization is a powerful query independent compilation and optimization technique for complex linear recursions in deductive databases [6, 7, 10, 8, 4]. It transforms a linear recursion into an n-chain recursion which consists of n chain predicates among which there is no shared variables. Normalization facilitates capturing more bindings and doing quantitative analysis, hence generating efficient query processing plans. However, the existing normalization methods are applicable only to single linear recursions. In this paper, we revise the concept of chain and n-chain recursion, and propose a novel method, called counting-based transformation, to transform a general multiple linear recursive program to single n-chain recursion. Based on this method, the existing evaluation methods which are applicable to single linear recursions can be applied also to multiple linear recursions.
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- 1.Beeri,C., Ramakrishnan, R.: “On the Power of Magic” Proc. ACM Symp. on Principles of Database Systems (PODS) pp.269–283 (1987)Google Scholar
- 2.Du, X., Ishii, N.: Optimizing Linear Recursive Formulas by Detaching Isolated Variables. IEICE Trans. Info. and Syst. Vol.E78-D, No.5, pp.579–585 (1995).Google Scholar
- 3.Du, X., Ishii, N.: Reducing the Arity of Predicates by Realigning Some Predicates. Proc. ICLP'95 Joint Workshop on Deductive Databases and Logic Programming. pp.57–69 (1995).Google Scholar
- 4.Du,X., Ishii,N.: Normalization of Linear Recursions based on Graph Transformation. Proc. Int'l Conf. CISMOD, LNCS 1009. pp.265–282 (Nov. 1995)Google Scholar
- 6.Han,J.: Compiling General Linear Recursions by Variable Connection Graph Analysis, Comput. Intell. 5, pp.12–31,(1989)Google Scholar
- 8.Lu,W., Lee,D.L., Han,J.: A Study on the Structure of Linear Recursion, IEEE Trans. KDE, Vol.6, No.5, pp.723–737 (1994)Google Scholar
- 10.Yong,C., Kim,H.J., et al.: Classification and Compilation of Linear Recursive Queries in Deductive Databases. IEEE Trans. KDE, Vol.4, No.1, pp.52–67 (1992)Google Scholar