摘要: 给一张表建主键,出现下列错误ORA-02437 :-违反主关键字主键列里面的数据有问题:有null或者有重复null:好判断重复:查询重复列的语句select * from (select count(*) as a ,t.courseId from course t group by t.courseId) b where b.a>1 阅读全文
posted @ 2012-11-10 20:18 NW_KNIFE 阅读(1253) 评论(0) 推荐(0) 编辑