启动和关闭mysql数据库连接

import mysql.connector

# 启动连接
try:
    conn = mysql.connector.connect(
        host="localhost",
        user="your_username",
        password="your_password",
        database="your_database"
    )
    print("连接成功")
    
    # 执行一些数据库操作
    cursor = conn.cursor()
    cursor.execute("SELECT * FROM your_table")
    results = cursor.fetchall()
    for row in results:
        print(row)
    
except mysql.connector.Error as err:
    print(f"连接失败: {err}")

finally:
    # 关闭连接
    if conn.is_connected():
        cursor.close()
        conn.close()
        print("连接已关闭")

import mysql.connector

try:
    with mysql.connector.connect(
        host="localhost",
        user="your_username",
        password="your_password",
        database="your_database"
    ) as conn:
        print("连接成功")
        
        with conn.cursor() as cursor:
            cursor.execute("SELECT * FROM your_table")
            results = cursor.fetchall()
            for row in results:
                print(row)
    
except mysql.connector.Error as err:
    print(f"连接失败: {err}")