求一个修改语句

[cyr11]

a
id atitle pic
1 aa bb
2 cc dd
3 dd rr


b
id btitle bpic
1 cc ee
2 aa tt

我用修改是

根据b btitle标题和a atitle一样修改a pic 值是 bpic值

结果是
a
id atitle pic
1 aa tt
2 cc ee
3 dd rr

[gxg353]

mysql> select * from a;
+------+--------+------+
| id   | atitle | pic  |
+------+--------+------+
|    1 | aa     | bb   | 
|    2 | cc     | dd   | 
|    3 | dd     | rr   | 
+------+--------+------+
3 rows in set (0.00 sec)

mysql> select * from b;
+------+--------+------+
| id   | btitle | bpic |
+------+--------+------+
|    1 | cc     | ee   | 
|    2 | aa     | tt   | 
+------+--------+------+
2 rows in set (0.00 sec)

mysql> update a ,b set a.pic=b.bpic where a.atitle=b.btitle ;
Query OK, 2 rows affected (0.00 sec)
Rows matched: 2  Changed: 2  Warnings: 0

mysql> select * from a;
+------+--------+------+
| id   | atitle | pic  |
+------+--------+------+
|    1 | aa     | tt   | 
|    2 | cc     | ee   | 
|    3 | dd     | rr   | 
+------+--------+------+
3 rows in set (0.00 sec)

[ACMAIN_CHM]

update a inner join b on a.atitle=b.btitle
set a.pic=b.bpic