使用带有mysql unix时间戳的sqlalchemy定义表

使用带有mysql unix时间戳的sqlalchemy定义表

我认为您显示的类型装饰器有几个问题。

1. impl

   应该

   sqlalchemy.types.Integer

   代替

   DateTime

   。
2. 装饰器应允许可空列。

这就是我的想法：

import datetime, timefrom sqlalchemy.types import TypeDecorator, DateTime, Integerclass IntegerDateTime(TypeDecorator):    """a type that decorates DateTime, converts to unix time on    the way in and to datetime.datetime objects on the way out."""    impl = Integer # In schema, you want these datetimes to        # be stored as integers.    def process_bind_param(self, value, _):        """Assumes a datetime.datetime"""        if value is None: return None # support nullability        elif isinstance(value, datetime.datetime): return int(time.mktime(value.timetuple()))        raise ValueError("Can operate only on datetime values. "   "Offending value type: {0}".format(type(value).__name__))    def process_result_value(self, value, _):        if value is not None: # support nullability return datetime.datetime.fromtimestamp(float(value))