说明：  万常选版数据库系统原理与设计实验教程第6-10次实验的参考答案，全部自己写的，经过验证。涉及数据库安全性、数据完整性、游标、存储过程、触发器、事务处理。
(The experiment6-10 solution for Wan s the principle of database systems and design of experiments tutorial , all write their own proven, to be verified. involve database security, data integrity, cursors, stored procedures, triggers, transaction processing The answers often choose Edition database system theory and design of experiments tutorial 1-4 times experiment, all written, validated. Including simple queries, complex queries, data definition operations, data update operation.)