mongodb - Return only array value in mongo projection -



mongodb - Return only array value in mongo projection -

is there way homecoming value of property in mongodb projection? instance, have document has property value array. want homecoming object query array only, not property: [ .. ]. example:

document:

db.test.insert({ name: "andrew", attributes: [ { title: "happy"}, { title: "sad" } ] });

query:

db.test.find({name: "andrew"},{attributes:1, "_id":0});

that returns:

{ "attributes" : [ { "title" : "happy" }, { "title" : "sad" } ] }

i want homecoming on array:

[ { title: "happy"}, { title: "sad" } ]

is there way that? thanks

json doesn't allow toplevel array normal query doesn't allow this. can aggregation framework:

> db.test.remove(); > db.test.insert({ name: "andrew", attributes: [ { title: "happy"}, { title: "sad" } ] }); > foo = db.test.aggregate( { $match: { name: "andrew" } }, { $unwind: "$attributes" }, { $project: { _id: 0, title: "$attributes.title" } } ); { "result" : [ { "title" : "happy" }, { "title" : "sad" } ], "ok" : 1 } > foo.result [ { "title" : "happy" }, { "title" : "sad" } ]

this however, not create cursor object find does.

mongodb

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