mysql-connector won't connect-CodePudding

import mysql.connector
from mysql.connector import Error

try:
    connection = mysql.connector.connect(host='localhost',
                                         database='Electronics',
                                         user='pynative',
                                         password='pynative@#29')
    if connection.is_connected():
        db_Info = connection.get_server_info()
        print("Connected to MySQL Server version ", db_Info)
        cursor = 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)
finally:
    if connection.is_connected():
        cursor.close()
        connection.close()
        print("MySQL connection is closed")

I know this should work because I have the code copied from a website. But for some reason it show s the error

'if connection.is_connected(): NameError: name 'connection' is not defined'

CodePudding user response：

If the mysql.connector.connect raisesan error, then connection variabe is never defined and you can't use it in the finally.

A solution is to initialize it as None and check that it isn't none before using it in the finally

connection = None
try:
    connection = mysql.connector.connect(host='localhost',
                                         database='Electronics',
                                         user='pynative',
                                         password='pynative@#29')
    if connection.is_connected():
        db_Info = connection.get_server_info()
        print("Connected to MySQL Server version ", db_Info)
        cursor = 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)
finally:
    if connection and connection.is_connected():
        cursor.close()
        connection.close()
        print("MySQL connection is closed")