insert 插入来自本表的数据

Question

mysql> desc a;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | int(11) | NO | PRI | 0 | |
| name | varchar(10) | YES | | NULL | |
| pwd | int(11) | YES | | NULL | |
| sss | int(11) | YES | | NULL | |
+-------+-------------+------+-----+---------+-------+

假设有如下值:
mysql> select * from a;
+----+-------+------+------+
| id | name | pwd | sss |
+----+-------+------+------+
| 2 | aaaa | 11 | 12 |
| 3 | bbbbb | 34 | 1 |
| 4 | cccc | 4 | 5 |
| 5 | wa | 32 | 22 |
| 10 | aaaa | 12 | 13 |
+----+-------+------+------+
请问 我要插入一条id为 12 其它字段的值和id为4的值一样 用SQL如何实现?
注意表结构 id为主键 不是自增的.
如果id为自增 可以用 insert into a select * from a where id=4实现.

Answer 1

insert into a(id,name,pwd,sss) select 12,a.name,a.pwd,a.sss from a where a.id = 4