如何选择PyMongo只有独特的记录？

Question

如何选择PyMongo只有独特的记录？

>>> db.houses.find({"street":{"$regex": "Fl", "$options":"i"}}).count()
107
>>> for item in db.houses.find({"street":{"$regex": "Fl", "$options":"i"}}):
...  print item["street"]
...
Flatbush Avenue
Flatbush Avenue
Flatbush Avenue
Flatlands Avenue
Flatlands Avenue
Flatlands Avenue
Flatlands Avenue
Flatlands Avenue
Flushing Avenue
Flushing Avenue
...more

如何在回复查询时仅获取"街道"的唯一记录？也就是说,为避免重复记录:

Flatbush Avenue
Flatlands Avenue
Flushing Avenue

Answer 1

根据文档 - Cursor.distinct应该做的伎俩:

db.houses.find({"street":{"$regex": "???", "$options":"i"}}).distinct("street")