标签：defer bsp inf http www. class cat alter def
使用oracl数据库用
ADD CONSTRAINT PRINF_NAME_UNIQUE UNIQUE (sname)
添加唯一性约束，出现问题，报错为：an alter table validating constraint failed because the table has duplicate key values.
百度了一下找到问题，只要改为
ALTER TABLE Students ADD CONSTRAINT PRINF_NAME_UNIQUE UNIQUE (sname) deferrable initially deferred NOVALIDATE;
详细的看链接：https://www.e-learn.cn/content/wangluowenzhang/492198
标签：defer bsp inf http www. class cat alter def
原文地址：https://www.cnblogs.com/tianqianlan/p/10561271.html
