摘要
本文给出拓广的左线性递归变换算法并证明其正确性．拓广的左线性递归中可以包含一个或多个ＩＤＢ谓词，它是左线性递归的一般化．和左线性递归计算算法一样，本文提供的算法遵循魔集的模式：首先改写规则，然后用半扑质的自底向上算法计算新规则．算法的有效性也在本文作简略讨论．
This paper presents an algorithm which transform a generalized left-linear recursion into more efficient rules,and shows the correctness of the given algorithm. A generalized left-linear recursion contains one or more IDB predicates and its definition is essentially generalized from that of left-linear recursions. As the algorithm for the evaluation of left - linear recursions, the algorithm we present here follows the magic-sets paradigm of a rewriting phase followed by semi -naive bottom-up evaluation. The efficinecy of the transformed rules is also discussed in this paper.
出处
《软件学报》
EI
CSCD
北大核心
1994年第1期56-61,共6页
Journal of Software
基金
河南省优秀中青年教师奖励基金
关键词
演绎数据库
线性递归
左线性递归
Deductive database
query processing
linear recursion
left - linear recursion.
