INSERT INTO SELECT

语法说明

INSERT INTO SELECT 语句从一个表复制数据，然后把数据插入到一个已存在的表中。且目标表中任何已存在的行都不会受影响。

语法结构

INSERT INTO table2 (column1, column2, column3, ...)
SELECT column1, column2, column3, ...
FROM table1
WHERE condition;

示例

create table t1(id int, name varchar(10));
insert into t1 values(1, 'a');
insert into t1 values(2, 'b');
insert into t1 values(3, 'c');
create table t2(id int, appname varchar(10), country varchar(10));
insert into t2 values(1, 'appone', 'CN');
insert into t2 values(2, 'apptwo', 'CN');
INSERT INTO t1 (name) SELECT appname FROM t2;
mysql> select * from t1;
+------+--------+
| id   | name   |
+------+--------+
|    1 | a      |
|    2 | b      |
|    3 | c      |
| NULL | appone |
| NULL | apptwo |
+------+--------+