python连接mysql数据库

python3连接mysql的方式：

def mysql_():
    conn = pymysql.connect(host='127.0.0.1', user='用户名', passwd='密码', db='数据库',
                           port=3306, charset='utf8',
                           cursorclass=pymysql.cursors.DictCursor)
    cur = conn.cursor()
    return conn,cur

if __name__=="__main__":
    conn,cur=mysql_()
    select_sql="select 列名 from 表名"
    cur.execute(select_sql)
    domain_list=cur.fetchall()
    for i in domain_list:
        print(i)