pymysql.connections.Connection(self,
host=None, # 要连接的主机地址
user=None, # 用于登录的数据库用户
password='', # 密码
database=None, # 要连接的数据库
port=0, # 端口,一般为 3306
unix_socket=None, # 选择是否要用unix_socket而不是TCP/IP
charset='', # 字符编码
sql_mode=None, # Default SQL_MODE to use.
read_default_file=None, # 从默认配置文件(my.ini或my.cnf)中读取参数
conv=None, # 转换字典
use_unicode=None, # 是否使用 unicode 编码
client_flag=0, # Custom flags to send to MySQL. Find potential values in constants.CLIENT.
cursorclass=<class 'pymysql.cursors.Cursor'>, # 选择 Cursor 类型
init_command=None, # 连接建立时运行的初始语句
connect_timeout=10, # 连接超时时间,(default: 10, min: 1, max: 31536000)
ssl=None, # A dict of arguments similar to mysql_ssl_set()'s parameters.For now the capath and cipher arguments are not supported.
read_default_group=None, # Group to read from in the configuration file.
compress=None, # 不支持
named_pipe=None, # 不支持
no_delay=None, #
autocommit=False, # 是否自动提交事务
db=None, # 同 database,为了兼容 MySQLdb
passwd=None, # 同 password,为了兼容 MySQLdb
local_infile=False, # 是否允许载入本地文件
max_allowed_packet=16777216, # 限制 `LOCAL DATA INFILE` 大小
defer_connect=False, # Don't explicitly connect on contruction - wait for connect call.
auth_plugin_map={}, #
read_timeout=None, #
write_timeout=None,
bind_address=None # 当客户有多个网络接口,指定一个连接到主机
)