select into from 與 insert into select 區別

1.INSERT INTO SELECT語句       語句形式爲：Insert into Table2(field1,field2,...) select value1,value2,... from Table1      要求目標表Table2必須存在，因爲目標表Table2已經存在，因此咱們除了插入源表Table1的字段外，還能夠插入常量。示例以下：INSERT INTO SELECT語句複製表數據   --1.建立測試表    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.建立測試數據    Insert into Table1 values('趙','asds','90')    Insert into Table1 values('錢','asds','100')    Insert into Table1 values('孫','asds','80')    Insert into Table1 values('李','asds',null)    GO    select * from Table2    --3.INSERT INTO SELECT語句複製表數據    Insert into Table2(a, c, d) select a,c,5 from Table1    GO    --4.顯示更新後的結果    select * from Table2    GO    --5.刪除測試表    drop TABLE Table1    drop TABLE Table2      2.SELECT INTO FROM語句      語句形式爲：SELECT vale1, value2 into Table2 from Table1      要求目標表Table2不存在，由於在插入時會自動建立表Table2，並將Table1中指定字段數據複製到Table2中。示例以下：SELECT INTO FROM建立表並複製表數據   --1.建立測試表    create TABLE Table1    (        a varchar(10),        b varchar(10),        c varchar(10),        CONSTRAINT [PK_Table1] PRIMARY KEY CLUSTERED        (            a ASC        )    ) ON [PRIMARY]    GO    --2.建立測試數據    Insert into Table1 values('趙','asds','90')    Insert into Table1 values('錢','asds','100')    Insert into Table1 values('孫','asds','80')    Insert into Table1 values('李','asds',null)    GO    --3.SELECT INTO FROM語句建立表Table2並複製數據    select a,c INTO Table2 from Table1    GO    --4.顯示更新後的結果    select * from Table2    GO    --5.刪除測試表    drop TABLE Table1    drop TABLE Table2