Python：我如何从datetime.timedelta对象中获取时间？

A mysql database table has a column whose datatype is time ( http://dev.mysql.com/doc/refman/5.0/en/time.html ). When the table data is accessed, Python returns the value of this column as a datetime.timedelta object. How do I extract the time out of this? (I didn't really understand what timedelta is for from the python manuals).

mysql数据库表有一个数据类型为time的列（http://dev.mysql.com/doc/refman/5.0/en/time.html）。访问表数据时，Python将此列的值作为datetime.timedelta对象返回。如何从中抽出时间？（我真的不明白timedelta是从python手册中得到的）。

E.g. The column in the table contains the value "18:00:00" Python-MySQLdb returns this as datetime.timedelta(0, 64800)

例如。表中的列包含值“18:00:00”Python-MySQLdb将其返回为datetime.timedelta（0,64800）

Please ignore what is below (it does return different value) -

请忽略下面的内容（它会返回不同的值） -

Added: Irrespective of the time value in the table, python-MySQLdb seems to only return datetime.timedelta(0, 64800).

补充：无论表中的时间值如何，python-MySQLdb似乎只返回datetime.timedelta（0,64800）。

Note: I use Python 2.4

注意：我使用Python 2.4

2 个解决方案

#1

It's strange that Python returns the value as a datetime.timedelta. It probably should return a datetime.time. Anyway, it looks like it's returning the elapsed time since midnight (assuming the column in the table is 6:00 PM). In order to convert to a datetime.time, you can do the following::

奇怪的是，Python将值返回为datetime.timedelta。它可能应该返回datetime.time。无论如何，看起来它正在返回自午夜起的经过时间（假设表中的列是下午6:00）。要转换为datetime.time，您可以执行以下操作::

value = datetime.timedelta(0, 64800)
(datetime.datetime.min + value).time()

datetime.datetime.min and datetime.time() are, of course, documented as part of the datetime module if you want more information.

当然，如果您需要更多信息，datetime.datetime.min和datetime.time（）会记录为datetime模块的一部分。

A datetime.timedelta is, by the way, a representation of the difference between two datetime.datetime values. So if you subtract one datetime.datetime from another, you will get a datetime.timedelta. And if you add a datetime.datetime with a datetime.timedelta, you'll get a datetime.datetime. That's how the code above works.

顺便提一下，datetime.timedelta是两个datetime.datetime值之间差异的表示。因此，如果从另一个中减去一个datetime.datetime，您将获得datetime.timedelta。如果您使用datetime.timedelta添加datetime.datetime，您将获得datetime.datetime。这就是上面代码的工作原理。

2 个解决方案

#1

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