How come my MongoDB query doesn't work?

Question

I'm using pymongo: http://api.mongodb.org/python/1.9%2B/index.html

for post in db.datasets.find({"set":"flickr"}).sort("num_favs","-1"):
    ...

How come I can't sort this? I'd like it sorted descending.

Answer 1

每个密钥对中的第二项必须为ASCENDING，DESCENDING或GEO2D

Answer 2

使用.sort("num_favs",-1)代替,"-1" 。