摘要: ORACLE中添加删除主键1、创建表的同时创建主键约束(1)无命名create table student (studentid int primary key not null,studentname varchar(8),age int);(2)有命名create table students ( studentid int , studentname varchar(8), age int, constraint yy primary key(studentid));2、删除表中已有的主键约束(1)有命名alter table students drop constraint yy;(2 阅读全文
posted @ 2013-11-19 16:15 绿茵飞狼 阅读(160) 评论(0) 推荐(0) 编辑