报错信息: com.mongodb.MongoWriteException: Invalid modifier specified $currentDate
$currentDate是在版本2.6.0的时候引进来的:
http://stackoverflow.com/questions/29022650/update-field-with-currentdate-on-pymongo-not-working
wdxxl@ubuntu:~$ mongo -version
MongoDB shell version: 2.4.9
解决方案: 升级版本
http://blog.csdn.net/ligaofeng/article/details/23415761