用外网怎么连接数据库

import pymysql
from sshtunnel import SSHTunnelForwarder

# SSH连接配置
ssh_host = 'your_ssh_server_ip'
ssh_port = 22
ssh_username = 'your_ssh_username'
ssh_password = 'your_ssh_password'

# 数据库连接配置
db_host = '127.0.0.1'
db_port = 3306
db_user = 'your_db_username'
db_password = 'your_db_password'
db_name = 'your_db_name'

# 创建SSH隧道
with SSHTunnelForwarder(
    (ssh_host, ssh_port),
    ssh_username=ssh_username,
    ssh_password=ssh_password,
    remote_bind_address=(db_host, db_port)
) as tunnel:
    # 数据库连接
    conn = pymysql.connect(
        host='127.0.0.1',
        port=tunnel.local_bind_port,
        user=db_user,
        password=db_password,
        db=db_name
    )
    
    # 执行查询
    cursor = conn.cursor()
    cursor.execute("SELECT * FROM your_table")
    results = cursor.fetchall()
    
    # 打印结果
    for row in results:
        print(row)
    
    # 关闭连接
    cursor.close()
    conn.close()