Python/postgres : Any advantage to converting mxDateTime to built in datetime objects?

Question

我继承的一些代码使用 Python 的 psycopg2 模块从 Postgres 数据库查询返回 mxDateTime 对象。我猜这种行为是出于历史原因，但想知道是否还有其他解释。鉴于我已经通过我继承的大型库具有 mxDateTime 依赖项，在对这些日期进行操作之前转换为内置日期时间数据类型是否有任何优势？

Answer 1

有很大的理由不改变它，这不是历史原因。内置的 Python 时间戳通常只有 32 位。

Postgresqls 时间戳:

min value 4713 BC

max value: 5874897 AD

http://www.postgresql.org/docs/current/static/datatype-datetime.html#DATATYPE-DATETIME-TABLE

Python 的:

classmethod date.fromtimestamp(timestamp)¶

... It’s common for this to be restricted to years from 1970 through 2038. Note that on non-POSIX systems that include leap seconds in their notion of a timestamp, leap seconds are ignored by fromtimestamp().

http://docs.python.org/library/datetime.html#datetime.date.fromtimestamp

在带有 Python 2.5 的 Windows 7 上:

>>>> date.fromtimestamp(0)
datetime.date(1969, 12, 31)
>>> date.fromtimestamp(-1)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: timestamp out of range for platform localtime() function