MySQL预处理和事务

$name='" or ""="'; 
 select * from stu where name=?; 
--==============================
mysql> select * from stu; 
+----+----------+------+------+---------+ 
| id | name     | sex  | age  | classid | 
+----+----------+------+------+---------+ 
|  1 | zhangsan |    1 |   20 | class113 | 
|  3 | wangwu   |    1 |   22 | class113 | 
|  4 | lisi     |    0 |   20 | class113 | 
|  5 | aaa      |    1 |   23 | class115 | 
|  6 | bbbb     |    1 |   42 | class113 | 
|  7 | ddd      |    0 |   21 | class115 | 
|  8 | ccac     |    1 |   26 | class113 | 
|  9 | eee      |    0 |   32 | class115 | 
| 10 | www      |    0 |   18 | class113 | 
| 11 | kkak     |    1 |   19 | class113 | 
| 12 | lll      |    0 |   26 | class115 | 
| 13 | uuau     |    0 |   24 | class113 | 
| 14 | yy       |    1 |   21 | class113 | 
| 15 | ttt      |    0 |   20 | class113 | 
+----+----------+------+------+---------+ 
14 rows in set (0.00 sec) 

mysql> prepare select_stu from 'select * from stu where name=?'; 
Query OK, 0 rows affected (0.03 sec) 
Statement prepared 

mysql> set @name='zhangsan'; 
Query OK, 0 rows affected (0.00 sec) 

mysql> execute select_stu using @name; 
+----+----------+------+------+---------+ 
| id | name     | sex  | age  | classid | 
+----+----------+------+------+---------+ 
|  1 | zhangsan |    1 |   20 | class113 | 
+----+----------+------+------+---------+ 
1 row in set (0.00 sec) 

mysql> set @name="' or ''='"; 
Query OK, 0 rows affected (0.00 sec) 
mysql> execute select_stu using @name; 
Empty set (0.02 sec)
--===============================
mysql> set autocommit=0; 
Query OK, 0 rows affected (0.00 sec) 

mysql> delete from stu where id>10; 
Query OK, 5 rows affected (0.03 sec) 


mysql> select * from stu; 
+----+----------+------+------+---------+ 
| id | name     | sex  | age  | classid | 
+----+----------+------+------+---------+ 
|  1 | zhangsan |    1 |   20 | class113 | 
|  3 | wangwu   |    1 |   22 | class113 | 
|  4 | lisi     |    0 |   20 | class113 | 
|  5 | aaa      |    1 |   23 | class115 | 
|  6 | bbbb     |    1 |   42 | class113 | 
|  7 | ddd      |    0 |   21 | class115 | 
|  8 | ccac     |    1 |   26 | class113 | 
|  9 | eee      |    0 |   32 | class115 | 
| 10 | www      |    0 |   18 | class113 | 
+----+----------+------+------+---------+ 
9 rows in set (0.00 sec) 

mysql> update stu set age=age+2 where id in(7,8,10); 
Query OK, 3 rows affected (0.00 sec) 
Rows matched: 3  Changed: 3  Warnings: 0 


mysql> select * from stu; 
+----+----------+------+------+---------+ 
| id | name     | sex  | age  | classid | 
+----+----------+------+------+---------+ 
|  1 | zhangsan |    1 |   20 | class113 | 
|  3 | wangwu   |    1 |   22 | class113 | 
|  4 | lisi     |    0 |   20 | class113 | 
|  5 | aaa      |    1 |   23 | class115 | 
|  6 | bbbb     |    1 |   42 | class113 | 
|  7 | ddd      |    0 |   23 | class115 | 
|  8 | ccac     |    1 |   28 | class113 | 
|  9 | eee      |    0 |   32 | class115 | 
| 10 | www      |    0 |   20 | class113 | 
+----+----------+------+------+---------+ 
9 rows in set (0.00 sec) 

mysql> rollback; 
Query OK, 0 rows affected (0.04 sec) 


mysql> select * from stu; 
+----+----------+------+------+---------+ 
| id | name     | sex  | age  | classid | 
+----+----------+------+------+---------+ 
|  1 | zhangsan |    1 |   20 | class113 | 
|  3 | wangwu   |    1 |   22 | class113 | 
|  4 | lisi     |    0 |   20 | class113 | 
|  5 | aaa      |    1 |   23 | class115 | 
|  6 | bbbb     |    1 |   42 | class113 | 
|  7 | ddd      |    0 |   21 | class115 | 
|  8 | ccac     |    1 |   26 | class113 | 
|  9 | eee      |    0 |   32 | class115 | 
| 10 | www      |    0 |   18 | class113 | 
| 11 | kkak     |    1 |   19 | class113 | 
| 12 | lll      |    0 |   26 | class115 | 
| 13 | uuau     |    0 |   24 | class113 | 
| 14 | yy       |    1 |   21 | class113 | 
| 15 | ttt      |    0 |   20 | class113 | 
+----+----------+------+------+---------+ 
14 rows in set (0.00 sec) 

mysql> commit; 
Query OK, 0 rows affected (0.00 sec)