首先创建四个临时表t1,t2,t3,t4,和他们相对应的索引 复制内容到剪贴板 代码: create table t1 as select * from user_objects; create table t2 as select * from user_objects; create table t3 as select * from user_objects; create table t4 as select * from user_objects; create unique inde