How can I query the value of an object rather than the key value pair in MongoDB - mongodb

Question

I've store an array on my user object which holds all of the data
{
_id: ObjectId(#############)
fname: 'Bob',
lname: 'Vargas',
data: [
// the data I want
]
}
I am using express to get his data like this:
db.users.findOne( { _id: ObjectId(#############) }, { data: 1, _id: 0 } );
but that is giving me an object rather than the array:
{ data: [ /* my data */ ]}
how can I get just the array?
UPDATE
app.get('/user/:id/data', function (req, res, next) {
db.users.findOne(
{ _id: mongojs.ObjectId(req.params.id) },
{ data: 1, _id: 0 },
function (err, userData) {
if (err) {
res.send(err);
}
res.json(userData);
}
);
});

Answer 1

Add projection to query result:
db.users.findOne( { _id: ObjectId(#############) }, {_id:0, data:1} )
Use 0 to exlude field from result (_id is included by default), and 1 to include field in result.
MongoDB returns object per document. But you can manually map objects on client side:
db.users.findOne( { _id: ObjectId(#############) }, {_id:0, data:1} )
.map(function(d){ return d.data; }))

Answer 2

MongoDB's findOne() will only return an object, not an array; thus the One. Instead you will need to receive it as and object and then get the value.
If you are doing this from mongo shell then there is no way around unless you want to move the data into its own collection. Otherwise you can get the array from the object in your application.
UPDATE:
in your express response, only encode the data value, like this
res.json(userData.data);