SELECT INTO FROM 与 insert into from

1.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，请注意vale1,vale2一定要是Table1有的字段，否则就会出错
。示例如下： 

 --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

如果像这样：

select count(*) into Table2 from table1

就会出错，因为Table1没有count(*)这个字段。

2、insert into from語句

语句形式为：Insert into Table2(field1,field2,...) select value1,value2,... from Table1

   --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

從Table1表中查詢出a,c數據插入到Table2表。