求一简单查询

Question

表A
CODE    NANEM ..................
1234    fdfdfd..................
2345    ........................表B
CODE    ........................
1234    ........................
5555    ........................我想要的结果就是 表A和表B CODE列的合集
:
结果为:
CODE    .........................
1234    ......................... 
2345    .........................
5555    .........................在线等

Answer 1

select * from A
union all
select * from B

Answer 2

我想要的结果就是 表A和表B CODE列的合集：
两表中有相同CODE的，NAME以哪个表为准？B表？

Answer 3

mysql> select * from a;
+------+--------------------------+
| code | namem                    |
+------+--------------------------+
| 1234 | fdfdfd.................. |
| 2345 | ........................ |
+------+--------------------------+
2 rows in set (0.00 sec)mysql> select * from b;
+------+--------------------------+
| code | namem                    |
+------+--------------------------+
| 1234 | ........................ |
| 5555 | ........................ |
+------+--------------------------+
2 rows in set (0.00 sec)mysql>
mysql> select * from a where code not in (select code from b)
    -> union
    -> select * from b
    -> order by code;
+------+--------------------------+
| code | namem                    |
+------+--------------------------+
| 1234 | ........................ |
| 2345 | ........................ |
| 5555 | ........................ |
+------+--------------------------+
3 rows in set (0.00 sec)mysql>