MongoDB query to return only embedded document
- by Matt
assume that i have a BlogPost model with zero-to-many embedded Comment documents. can i query for and have MongoDB return only Comment objects matching my query spec?
eg, db.blog_posts.find({"comment.submitter": "some_name"}) returns only a list of comments.
edit: an example:
import pymongo
connection = pymongo.Connection()
db = connection['dvds']
db['dvds'].insert({'title': "The Hitchhikers Guide to the Galaxy",
'episodes': [{'title': "Episode 1", 'desc': "..."},
{'title': "Episode 2", 'desc': "..."},
{'title': "Episode 3", 'desc': "..."},
{'title': "Episode 4", 'desc': "..."},
{'title': "Episode 5", 'desc': "..."},
{'title': "Episode 6", 'desc': "..."}]})
episode = db['dvds'].find_one({'episodes.title': "Episode 1"},
fields=['episodes'])
in this example, episode is:
{u'_id': ObjectId('...'),
u'episodes': [{u'desc': u'...', u'title': u'Episode 1'},
{u'desc': u'...', u'title': u'Episode 2'},
{u'desc': u'...', u'title': u'Episode 3'},
{u'desc': u'...', u'title': u'Episode 4'},
{u'desc': u'...', u'title': u'Episode 5'},
{u'desc': u'...', u'title': u'Episode 6'}]}
but i just want:
{u'desc': u'...', u'title': u'Episode 1'}
