SQL在递归查询和逻辑谓词上的扩充  

THE EXTENSION OF RECURSIVE QUERY AND LOGICAL PREDICATE IN SQL

作　　者：汪卫[1] 丁宝康[1] 

机构地区：[1]上海复旦大学计算机系

出　　处：《计算机研究与发展》1996年第8期591-598,共8页Journal of Computer Research and Development

摘　　要：本文讨论了对ＳＱＬ语言的递归查询和逻辑谓词功能上的扩充方法。给出了递归查询的关系代数表达式，并就考虑路径的递归查询和不考虑路径的递归查询两方面对ＳＱＬ在句法和算法上，对ＳＱＬ中逻辑谓词扩充的理论、句法和算法进行了讨论。In this paper, we discuss a method to add the function of recursive query and the concept of logic predicate to SoL. In the first part, we give the relation algebra expression of recursive query, and the discussion of syntax and algorithm of two kinds of recursive query: 1. Considering path; 2. Not considering path. In the second part, we give the theory, syntax and algorithm of adding logic predicate to SoL.

关 键 词：SQL语言 递归查询 逻辑谓词 数据库 

分 类 号：TP311.13[自动化与计算机技术—计算机软件与理论]