mongodb 更换mysql

以下是将MongoDB数据迁移到MySQL的示例代码：

from pymongo import MongoClient
import mysql.connector

# 连接MongoDB数据库
mongo_client = MongoClient('mongodb://localhost:27017')
mongo_db = mongo_client['mydatabase']
mongo_collection = mongo_db['mycollection']

# 连接MySQL数据库
mysql_connection = mysql.connector.connect(
    host='localhost',
    user='your_username',
    password='your_password',
    database='mydatabase'
)
mysql_cursor = mysql_connection.cursor()

# 从MongoDB读取数据
mongo_documents = mongo_collection.find()

# 将数据插入到MySQL中
for document in mongo_documents:
    field1_value = document['field1']
    field2_value = document['field2']
    field3_value = document['field3']
    mysql_cursor.execute("INSERT INTO mycollection (field1, field2, field3) VALUES (%s, %s, %s)", (field1_value, field2_value, field3_value))
    mysql_connection.commit()