增(INSERT)
IF OBJECT_ID('student2','U') IS NOT NULLDROP TABLE student2create table student2(sid int primary key identity(20,5),sname nchar(8) not null,ssex nchar(1) constraint DF_SEX DEFAULT('女'))insert into student2(sname,ssex) values ('张三','男');insert into student2(ssex,sname) values ('男','钱一');--可以打乱字段顺序,但值必须与字段一一对应。insert into student2 values ('李四','女');--可以省略列名,但是赋值必须按照字段顺序。insert into student2 values ('王五','女'),('周六','男'); --用values 插入多列。insert into student2 select '吴起','男'; --用select 插入列insert into student2 select '郑八','女' union select '关九','男' --用select 插入多列SET IDENTITY_INSERT CESHI.DBO.student2 ON;/*insert into student2 values ('9','李四','女'); */ --报错insert into student2 (sid,sname,ssex)values ('9','李四','女'); --'9'虽为字符串型,但是可以转化为int型 insert into student2 (sid,sname,ssex)values (12,'李四',default); --使用default来代替默认值 SET IDENTITY_INSERT CESHI.DBO.student2 Off;select * from student2
IF OBJECT_ID('student3','U') IS NOT NULLDROP TABLE student3create table student3 --创建表3与表2一致(sid int primary key identity(20,5),sname nchar(8) not null,ssex nchar(1))IF OBJECT_ID('student4','U') IS NOT NULLDROP TABLE student4create table student4 --创建表4与表2除自增以外,其他一致(sid int primary key ,sname nchar(8) not null,ssex nchar(1))go SET IDENTITY_INSERT CESHI.DBO.student3 ON; --如果student3没有自增限制,则无需执行此操作--同一时间只能打开一个‘IDENTITY_INSERT’。如果此时执行 set IDENTITY_INSERT student4 on 则会报错。insert into student3(ssex ,sid ,sname ) select ssex ,sid ,sname from student2 set IDENTITY_INSERT student3 off insert into student4 select * from student2 select * into student5 from student2 --创建新表5,将表2所有内容传入。select * from student2select * from student3 select * from student4select * from student5
student2、 student3、 student4、student5查询结果一致。