MySQLdb执行向表中插入数据

Question

我是MySql和MySQLdb的新手。但我已经试了好几个小时来解决这个问题。你知道吗

我有一张这样的桌子：

mysql> DESCRIBE users;

+----------+-------------+------+-----+---------+----------------+
| Field    | Type        | Null | Key | Default | Extra          |
+----------+-------------+------+-----+---------+----------------+
| id       | int(11)     | NO   | PRI | NULL    | auto_increment |
| username | varchar(25) | YES  |     | NULL    |                |
| password | varchar(25) | YES  |     | NULL    |                |
+----------+-------------+------+-----+---------+----------------+

代码部分：

def connect_db():
    conn = MySQLdb.connect(user='root',
                            passwd='',
                            db='flask',
                            host='localhost')
    return conn


cur = connect_db().cursor()


cur.execute("DROP TABLE IF EXISTS users")
cur.execute("CREATE TABLE users(id INT PRIMARY KEY AUTO_INCREMENT, \
                username VARCHAR(25), password VARCHAR(25))")

str = "INSERT INTO users ('id', 'username', 'password') VALUES (NULL, %s, %s)"

cur.execute(str % ('admin', 'password'))

我犯了这样一个错误：

> Traceback (most recent call last):   File
> "C:\Users\Emil\Desktop\flaskr\flaskr.py", line 29, in <module>
>     cur.execute(str % ('admin', 'password'))   File "C:\Python27\lib\site-packages\MySQLdb\cursors.py", line 202, in
> execute
>     self.errorhandler(self, exc, value)   File "C:\Python27\lib\site-packages\MySQLdb\connections.py", line 36, in
> defa lterrorhandler
>     raise errorclass, errorvalue
> _mysql_exceptions.ProgrammingError: (1064, "You have an error in your SQL synta ; check the manual that corresponds to your MySQL server
> version for the right yntax to use near ''id', 'username', 'password')
> VALUES (NULL, admin, password)  at line 1")

我想我的INSERT命令有问题。我不知道该怎么做，我试着在谷歌上搜索可能有用的内容。你知道吗

Answer 1

以下是使用当前解决方案得到的查询结果：

INSERT INTO users ('id', 'username', 'password') VALUES (NULL, admin, password)

如您所见，admin和password之间没有引号-这就是ProgrammingError异常的原因。你知道吗

除此之外，通过字符串格式插入查询参数会使您的代码容易受到SQL注入的攻击。你知道吗

---

相反，参数化查询：

query = """
    INSERT INTO 
        users 
        ('id', 'username', 'password') 
    VALUES 
        (NULL, %s, %s)
"""

cur.execute(query, ('admin', 'password'))