Python MySQL Connector初始化后遇AttributeError：connection对象无对应属性

问题重现 #

运行Python代码使用MySQL Connector时触发AttributeError，错误日志如下：

File "/Users/y.k./Desktop/MyProjects/Perosnal Coding projects/S_C.b/database/db_config.py", line 24, in get_connection
print(self.db_connection)
AttributeError: 'connection' object has no attribute 'connection'. Did you mean: 'get_connection'?

对应的代码实现：

import mysql.connector
from mysql.connector import Error

class connection:

   def __init__(self):
       self.db_connection;
       try:
             self.db_connection = mysql.connector.connect(host='localhost', database='S-Cb_db', user='root', password='root')
             if self.db_connection.is_connected():
                   db_Info = self.db_connection.get_server_info()
                   print("Connected to MySQL Server version ",  db_Info)
                   cursor = self.db_connection.cursor()
                   cursor.execute("select database();")
                   record = cursor.fetchone()
                   print("You're connected to database: ", record)
       except Error as e:
             print("Error while connecting to MySQL", e)
        
   def get_connection(self):
       return self.db_connection;

需要通过get_connection函数在db_controller.py中获取连接并创建游标执行查询。

问题原因 #

1. 命名冲突导致混淆：自定义类名connection与mysql.connector.connect()返回的连接对象类名完全一致，容易在调用时产生混淆，误写属性名。
2. 调用代码存在错误：错误日志提示'connection' object has no attribute 'connection'，说明你在db_controller.py中调用时，错误地尝试访问实例的connection属性（比如写成conn.connection），但你的类实例并没有这个属性，正确的应该是调用get_connection()方法或者访问db_connection属性。
3. 初始化代码有无效语句：__init__方法中的self.db_connection;是无意义的空语句，虽然不会直接引发错误，但属于冗余代码。

解决建议 #

1. 重命名自定义类，避免命名冲突 #

将自定义类名改为DBConnection这类更清晰、不会与内置类重名的名称，减少混淆概率：

import mysql.connector
from mysql.connector import Error

class DBConnection:  # 修改类名
   def __init__(self):
       try:
             self.db_connection = mysql.connector.connect(host='localhost', database='S-Cb_db', user='root', password='root')
             if self.db_connection.is_connected():
                   db_Info = self.db_connection.get_server_info()
                   print("Connected to MySQL Server version ",  db_Info)
                   cursor = self.db_connection.cursor()
                   cursor.execute("select database();")
                   record = cursor.fetchone()
                   print("You're connected to database: ", record)
       except Error as e:
             print("Error while connecting to MySQL", e)
             self.db_connection = None  # 连接失败时显式赋值为None，避免后续调用报错
        
   def get_connection(self):
       return self.db_connection

2. 修正db_controller.py中的调用代码 #

确保正确调用get_connection()方法获取连接：

from db_config import DBConnection  # 对应修改后的类名

# 创建连接实例
db_conn = DBConnection()
# 获取连接对象
connection = db_conn.get_connection()

# 检查连接是否有效后创建游标执行查询
if connection:
    cursor = connection.cursor()
    cursor.execute("SELECT * FROM your_table")
    results = cursor.fetchall()
    # 处理查询结果
    cursor.close()

3. 优化连接失败的处理逻辑 #

在__init__的异常捕获中，给self.db_connection赋值为None，这样后续调用get_connection()时可以判断连接是否成功，避免出现新的属性错误。

内容的提问来源于stack exchange，提问作者Youssof. K.