mysql.connector.errors.ProgrammingError: 1054 (42S22): Unknown column 'X' in 'where clause'

Question

这是我的脚本：

import mysql.connector
def loginsystem():
    db = mysql.connector.connect(host="127.0.0.1",
                                 user="root",
                                 passwd="",
                                 db="dbpython")

    cursor = db.cursor()

    loop = 'true'
    while (loop == 'true'):
        username = str(input("Username : "))
        password = str(input("Password : "))

        if (cursor.execute("SELECT * FROM users WHERE username = %s AND password = %s"%(username,password))):

            print("Logged İn")
        else:
            print("Failure")
    db.commit()
loginsystem()

我正在安装在线系统，但是我遇到了登录系统的问题。如何修复 "Unknown column 'x' in where clause" 或者您有任何其他代码建议？

if (cursor.execute("SELECT * FROM users WHERE (username =?  password = ?) VALUES(?,?)"(username,password))):

我试过用这个方法，但是没有

Traceback (most recent call last):
  File "C:/Users/artun/PycharmProjects/DENEMELER/Login System.py", line 21, in <module>
    loginsystem()
  File "C:/Users/artun/PycharmProjects/DENEMELER/Login System.py", line 15, in loginsystem
    if (cursor.execute("SELECT * FROM users WHERE username = %s AND password = %s"%(username,password))):
  File "C:\Users\artun\PycharmProjects\DENEMELER\venv\lib\site-packages\mysql\connector\cursor.py", line 569, in execute
    self._handle_result(self._connection.cmd_query(stmt))
  File "C:\Users\artun\PycharmProjects\DENEMELER\venv\lib\site-packages\mysql\connector\connection.py", line 553, in cmd_query
    result = self._handle_result(self._send_cmd(ServerCmd.QUERY, query))
  File "C:\Users\artun\PycharmProjects\DENEMELER\venv\lib\site-packages\mysql\connector\connection.py", line 442, in _handle_result
    raise errors.get_exception(packet)
mysql.connector.errors.ProgrammingError: 1054 (42S22): Unknown column 'oziboran123' in 'where clause'

Process finished with exit code 1

这是代码的输出，但我预计代码的输出是 "Logged In" 或 "Failure"

Answer 1

考虑参数化而不是字符串插值，后者涉及 two-step 准备语句的过程，然后执行绑定参数。下面使用 execute 调用的两个参数：cursor.execute(query, params)。此外，user 和 password 是 MySQL 中的 reserved words，应使用反引号进行转义。

请注意 mysql.connector API 的参数占位符 %s 不应与 Python 的模字符串格式符号混淆（顺便说一句是少preferred string formatting method in Python for more preferred str.format).

# PREPARED STATEMENT
sql = """SELECT * FROM `users`
         WHERE `username` = %s AND `password` =%s
      """

# EXECUTE WITH PARAMS
cursor.execute(sql, (username, password))

Answer 2

试试下面的代码：

 """SELECT * FROM `users` WHERE `username` '{}' AND `password` '{}'""".format(username,password))

mysql.connector.errors.ProgrammingError: 1054 (42S22): Unknown column 'X' in 'where clause'

mysql.connector.errors.ProgrammingError: 1054 (42S22): Unknown column 'X' in 'where clause'

python

mysql-python