MySQL（关系型数据库）

-- 插入数据
INSERT INTO users (name, email) VALUES ('张三', 'zhang@example');

-- 查询数据
SELECT * FROM users WHERE name = '张三';

-- 更新数据
UPDATE users SET email = 'new@example' WHERE name = '张三';

-- 删除数据
DELETE FROM users WHERE name = '张三';

pip install mysql-connector-python==9.1.0

docker run -d --name mysql-dev -e MYSQL_ROOT_PASSWORD=123456 -e MYSQL_DATABASE=agent_db -p 3306:3306 mysql:9.0

import mysql.connector
import os

# 1. 连接数据库
conn = mysql.connector.connect(
    host=os.getenv("MYSQL_HOST", "localhost"),
    user=os.getenv("MYSQL_USER", "root"),
    password=os.getenv("MYSQL_PASSWORD", "123456"),
    database=os.getenv("MYSQL_DATABASE", "agent_db"),
    charset="utf8mb4"
)
cursor = conn.cursor(dictionary=True)

# 2. 建表
cursor.execute("""
CREATE TABLE IF NOT EXISTS chat_logs (
    id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    role ENUM('user', 'agent') NOT NULL,
    content TEXT NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    INDEX idx_user (user_id),
    INDEX idx_time (created_at)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4
""")

# 3. 用事务插入一轮对话（用户提问 + Agent 回复）
try:
    cursor.execute("START TRANSACTION")
    cursor.execute(
        "INSERT INTO chat_logs (user_id, role, content) VALUES (%s, %s, %s)",
        (1, "user", "Python 的装饰器怎么用？")
    )
    cursor.execute(
        "INSERT INTO chat_logs (user_id, role, content) VALUES (%s, %s, %s)",
        (1, "agent", "装饰器本质上是一个接收函数并返回函数的高阶函数……")
    )
    conn.commit()
    print("[OK] 对话已保存")
except Exception as e:
    conn.rollback()
    print(f"[ERROR] 保存失败: {e}")

# 4. 查询某用户的最近对话
cursor.execute(
    "SELECT role, content, created_at FROM chat_logs WHERE user_id = %s ORDER BY created_at",
    (1,)
)
for row in cursor.fetchall():
    print(f"[{row['role']}] {row['content']}")

cursor.close()
conn.close()

[OK] 对话已保存
[user] Python 的装饰器怎么用？
[agent] 装饰器本质上是一个接收函数并返回函数的高阶函数……