基于ALPHA语言的复杂查询SQL语句生成  

SQL Statement Generation for Complex Queries Based on ALPHA Language

作　　者：汪洋 WANG Yang(School of Computer & Information, Anqing Normal University, Anqing 246133, China)

机构地区：[1]安庆师范大学计算机与信息学院,安徽安庆246133

出　　处：《安庆师范大学学报（自然科学版）》2018年第4期123-125,共3页Journal of Anqing Normal University(Natural Science Edition)

摘　　要：用SQL语言表达复杂查询,是数据库教学中的一个重点和难点,但对数据库理论的初学者是个挑战。文章提出了一个复杂查询的SQL语句生成框架,首先将复杂查询用ALPHA语言表示,然后利用逻辑谓词等价变换理论,将ALPHA语句中的全称量词和逻辑蕴含进行等价变换,再使用ALPHA语言向SQL语言变换生成算法生成SQL查询。该框架在多年的教学实践中得到了检验,并取得了较好的教学效果。In database teaching,it is a key and difficult point to express complex query in SQL language,and it is a challenge for beginners of database theory.This paper proposes a complex query of SQL statement generated framework.Firstly,complex queries are expressed with ALPHA language.Then,all universal quantifier and logic implication in ALPHA statements are equivalently transformed by using the theory of logical predicate equivalent transformation.At last,SQL query statements are generated with transformation generation algorithm from ALPHA to SQL.The framework has been tested in teaching practice for many years and has achieved good teaching effect.

关 键 词：数据库 复杂查询 ALPHA SQL 谓词等价变换 

分 类 号：G642[文化科学—高等教育学]