SELECT * INTO xx FROM x0

时间:2023-11-25 12:11:26
insert into a select * from b;--向存在表中插入数据,如果不存在表a报错。 

select * into a from b;--创建新表的同时插入数据,如果表a存在,报错。

select into from 与 insert into select 区别鉴赏

SELECT * INTO xx FROM x0
   1.INSERT INTO SELECT语句       语句形式为:Insert into Table2(field1,field2,...) select value1,value2,... from Table1

      要求目标表Table2必须存在,由于目标表Table2已经存在,所以我们除了插入源表Table1的字段外,还可以插入常量。示例如下:

INSERT INTO SELECT语句复制表数据   --1.创建测试表    create TABLE Table1    (        a varchar(10),        b varchar(10),        c varchar(10),        CONSTRAINT [PK_Table1] PRIMARY KEY CLUSTERED        (            a ASC        )    ) ON [PRIMARY]

    create TABLE Table2    (        a varchar(10),        c varchar(10),        d int,        CONSTRAINT [PK_Table2] PRIMARY KEY CLUSTERED        (            a ASC        )    ) ON [PRIMARY]    GO    --2.创建测试数据    Insert into Table1 values('赵','asds','90')    Insert into Table1 values('钱','asds','100')    Insert into Table1 values('孙','asds','80')    Insert into Table1 values('李','asds',null)    GO    select * from Table2

    --3.INSERT INTO SELECT语句复制表数据    Insert into Table2(a, c, d) select a,c,5 from Table1    GO

    --4.显示更新后的结果    select * from Table2    GO    --5.删除测试表    drop TABLE Table1    drop TABLE Table2

      2.SELECT INTO FROM语句

      语句形式为:SELECT vale1, value2 into Table2 from Table1

      要求目标表Table2不存在,因为在插入时会自动创建表Table2,并将Table1中指定字段数据复制到Table2中。示例如下:

SELECT INTO FROM创建表并复制表数据   --1.创建测试表    create TABLE Table1    (        a varchar(10),        b varchar(10),        c varchar(10),        CONSTRAINT [PK_Table1] PRIMARY KEY CLUSTERED        (            a ASC        )    ) ON [PRIMARY]    GO

    --2.创建测试数据    Insert into Table1 values('赵','asds','90')    Insert into Table1 values('钱','asds','100')    Insert into Table1 values('孙','asds','80')    Insert into Table1 values('李','asds',null)    GO

    --3.SELECT INTO FROM语句创建表Table2并复制数据    select a,c INTO Table2 from Table1    GO

    --4.显示更新后的结果    select * from Table2    GO    --5.删除测试表    drop TABLE Table1    drop TABLE Table2

SELECT * INTO xx FROM x0

SELECT * INTO xx FROM x0