分布式关系型数据库年末活动

# 假设使用Python和某个分布式数据库库
from distributed_db import TransactionManager

tm = TransactionManager()

try:
    with tm.begin_transaction():
        node1.execute("UPDATE account SET balance = balance - 100 WHERE id = 1")
        node2.execute("UPDATE account SET balance = balance + 100 WHERE id = 2")
except Exception as e:
    tm.rollback()
    print(f"Transaction failed: {e}")

import redis
import pymysql

r = redis.Redis(host='localhost', port=6379, db=0)

def get_user_data(user_id):
    data = r.get(f"user:{user_id}")
    if data is None:
        conn = pymysql.connect(host='db_host', user='user', password='password', db='dbname')
        cursor = conn.cursor()
        cursor.execute("SELECT * FROM users WHERE id = %s", (user_id,))
        data = cursor.fetchone()
        r.setex(f"user:{user_id}", 3600, data)  # Cache for 1 hour
    return data