求一个Mysql的两个表间取数据的SQL语句

有两个表结构完全相同的表m1（mid，vipid）和m2（mid,vipid）,只是两表中的数据记录数不同，现在要求用SQL语句实现：取出两表中vipid不同的数据记录，把这些数据写入表m中，望高手赐教，怎么对两个表得到的结果集进行处理，谢谢！

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既然相同 为什么要哦设计两个表呢？

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lz 可以用个左连接 left join 试试看。

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SQL code:

mysql> create table tab_B(id int primary key auto_increment,username varchar(20
);
Query OK, 0 rows affected (0.09 sec)

mysql> insert into tab_A values('A');
ERROR 1136 (21S01): Column count doesn't match value count at row 1
mysql> insert into tab_A(username) values('A');
Query OK, 1 row affected (0.05 sec)

mysql> insert into tab_A(username) values('B');
Query OK, 1 row affected (0.05 sec)

mysql> insert into tab_B(username) values('C');
Query OK, 1 row affected (0.05 sec)

mysql> insert into tab_B(username) values('D');
Query OK, 1 row affected (0.05 sec)

mysql> [color=#FF0000]select * from tab_a union all select * from tab_b;[/color]
+----+----------+
| id | username |
+----+----------+
| 1 | A |
| 2 | B |
| 1 | C |
| 2 | D |
+----+----------+
4 rows in set (0.00 sec)

mysql>

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SQL code:

mysql> create table tab_B(id int pr