PROLOG—DBMS系统实现中的子句间优化技术

THE INTER-CLAUSE OPTIMIZATION TECHNIQUE IN THE IMPLEMENTATION OF PROLOG-DBMS SYSTEMS

实用ＰＲＯＬＯＧ—ＤＢＭＳ系统实现中的首要问题是要保证系统的正确性．然而，从数据库中提取冗余数据不但严重地影响系统的效率，而且影响系统的正确性．本文所提出的子句间优化技术可以解决这一问题．因为采用这一技术可以保证仅从数据库中提取有用事实并且没有任何元组多于一次被提取．

In the implementation of practical PROLOG-DBMS systems,the key issue is to maintain its correctness which is,unfortunately,often affected by extracting redundant facts from data base management systems.This paper presents a new technique called 'inter-clause optimization' which can not only keep the system correct but also increase its efficiency by guaranteeing that only useful facts are loaded from DBMS and no fact is loaded more than once.