Python连接器上传文件时出现后端错误

检查文件路径是否正确、文件大小是否超过上传限制、目标文件夹是否存在等问题。同时，也应该加上异常处理来捕获可能的错误信息，以便进一步调试。以下是一个示例代码：

import mysql.connector
from mysql.connector import errorcode
from mysql.connector import errors
from mysql.connector import FieldType

# import necessary modules for file upload
import os
from flask import Flask, request, redirect, url_for
from werkzeug.utils import secure_filename

# create a Flask app
app = Flask(__name__)

# set the maximum file size to be uploaded in bytes
app.config['MAX_CONTENT_LENGTH'] = 1 * 1024 * 1024

# define the path where files will be uploaded
UPLOAD_FOLDER = '/path/to/folder'
app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER

# define the allowed extensions for uploaded files
ALLOWED_EXTENSIONS = {'txt', 'pdf', 'png', 'jpg', 'jpeg', 'gif'}

# function to check if an uploaded file has an allowed extension
def allowed_file(filename):
    return '.' in filename and \
           filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS

# function to handle file upload requests
@app.route('/upload', methods=['POST'])
def upload_file():
    try:
        # get the file from the request
        file = request.files['file']
        
        # check if the file is allowed
        if file and allowed_file(file.filename):
            # secure the filename and save to disk
            filename = secure_filename(file.filename)
            filepath = os.path.join(app.config['UPLOAD_FOLDER'], filename)
            file.save(filepath)
            # upload the file to the database using mysql.connector
            cnx = mysql.connector.connect(user='user', password='password', host='127.0.0.1', database='database')
            cursor = cnx.cursor()
            insert_query = "INSERT INTO files (filename, filepath) VALUES (%s, %s)"
            cursor.execute(insert_query, (filename, filepath))
            cnx.commit()
            cursor.close()
            cnx.close()
            return "File uploaded successfully"
        else:
            return "Invalid file"
    except mysql.connector.Error as err