尝试在 Python 中比较日期时，我注意到一些非常奇怪的行为。我正在尝试使用日期来检查是否将项目添加到 MySQL 数据库(使用 mysqldb 库)，并且在比较日期时，我遇到了奇怪的行为:
代码是:
latestDate = pullDateFromTable() #pull the latest item from the table
for transaction in transactions:
print "Transaction Time:",transaction.date
print "Latest Entry:",latestDate
if transaction.date > latestDate:
print "Transaction is new, added product"
#insert item to MySQL database
else:
print "Old transaction, did not add product"
输出是:
Transaction Time: Thu Oct 4 11:42:25 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Old transaction, did not add product
Transaction Time: Wed Oct 3 22:11:48 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 19:32:56 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 17:46:35 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 17:46:35 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 17:46:35 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 16:25:06 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 14:00:48 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 11:46:20 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 11:46:20 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 11:22:37 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 09:05:13 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 09:05:13 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Wed Oct 3 09:05:13 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Tue Oct 2 07:38:25 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Transaction is new, added product
Transaction Time: Mon Oct 1 17:39:52 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Old transaction, did not add product
Transaction Time: Mon Oct 1 15:05:29 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Old transaction, did not add product
Transaction Time: Sun Sep 30 20:56:38 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Old transaction, did not add product
Transaction Time: Sun Sep 30 09:52:09 2012
Latest Entry: Thu Oct 4 11:42:25 2012
Old transaction, did not add product
您会注意到周二或周三(10 月 2 日和 3 日)的日期大于最晚的日期(10 月 4 日)，但 9 月或 10 月 1 日的日期小于。
对为什么会这样有任何想法吗？
请您参考如下方法:
您的日期似乎是字符串，并且正在按字母顺序进行比较。 W 在 T 之后。
