PROLOG-DBMS系统的数据库维护

DATABASE MAINTENANCE IN PROLOG DBMS

数据库查询、更新、维护是ＰＲＯＬＯＧ－ＤＢＭＳ系统的基本功能．优化方法，例如子句间优化技术，是使系统实用化的关键．在执行数据库更新操作时，优化技术引入的缓存数据库和原数据库可能产生数据不一致．文中分析了更新数据和查询历史之间的逻辑关系，指出一致性的约束条件，讨论了在单用户情况下数据库维护的有效策略．

Database query,revision and maintenance are the basic functions of the PROLOG DBMS system.An optimization technique,such as inter clause optimization,is the key to make the system practical.When a database revision operation is executed,the source database and the cache database produced for optimization will probably be inconsistent.The logical relationship between the revision data and the history query is analyzed and the constraint conditions are pointed out in the paper.Some effective database maintenance strategies for a single user are also discussed.