select into 和 insert into select 全表复制sql语句
select into 和 insert into select 全表复制sql语句 有需要的朋友可参考一下。
Insert是T-sql中常用语句,Insert INTO table(field1,field2,...) values(value1,value2,...)这种形式的在应用程序开发中必不可少。但我们在开发、测试过程中,经常会遇到需要表复制的情况,如将 一个table1的数据的部分字段复制到table2中,或者将整个table1复制到table2中,这时候我们就要使用SELECT INTO 和 INSERT INTO SELECT 表复制语句了。
区别
代码如下 | 复制代码 |
select * into destTbl from srcTbl insert into destTbl(fld1, fld2) select fld1, 5 from srcTbl |
以上两句都是将 srcTbl 的数据插入到 destTbl,但两句又有区别的。
第一句(select into from)要求目标表(destTbl)不存在,因为在插入时会自动创建。
第二句(insert into select from)要求目标表(destTbl)存在,由于目标表已经存在,所以我们除了插入源表(srcTbl)的字段外,还可以插入常量
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:
代码如下 | 复制代码 |
CREATE PROC getBusinessLineHistory |
INSERT INTO SELECT语句复制表数据
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
代码如下 | 复制代码 |
--1.创建测试表 --2.创建测试数据 --3.SELECT INTO FROM语句创建表Table2并复制数据 --4.显示更新后的结果 |
注意
表中没有记录返回时出错,表中有多条记录返回时也出错,用异常保护。
代码如下 | 复制代码 |
declare |
同时给多个变量赋值没有问题:
select 字段1,字段2,字段3 into 变量1,变量2,变量3 from 表名 where...

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