mysql分库join

import mysql.connector

# 连接用户数据库
user_db = mysql.connector.connect(
    host="user_db_host",
    user="user_db_user",
    password="user_db_password",
    database="user_db_name"
)

# 连接订单数据库
order_db = mysql.connector.connect(
    host="order_db_host",
    user="order_db_user",
    password="order_db_password",
    database="order_db_name"
)

# 查询用户信息
user_cursor = user_db.cursor()
user_cursor.execute("SELECT id, name FROM user WHERE id = %s", (user_id,))
user_result = user_cursor.fetchone()

# 查询订单信息
order_cursor = order_db.cursor()
order_cursor.execute("SELECT user_id, amount FROM `order` WHERE user_id = %s", (user_id,))
order_results = order_cursor.fetchall()

# 在应用层实现JOIN
user_orders = []
for order in order_results:
    user_orders.append({
        "user_id": user_result[0],
        "user_name": user_result[1],
        "order_id": order[0],
        "amount": order[1]
    })

# 关闭连接
user_cursor.close()
order_cursor.close()
user_db.close()
order_db.close()

print(user_orders)