MongoDB - Select multiple sub-dicuments from array using $elemMatch - arrays

Question

I have a collection like the following:-
{
_id: 5,
"org_name": "abc",
"items": [
{
"item_id": "10",
"data": [
// Values goes here
]
},
{
"item_id": "11",
"data": [
// Values goes here
]
}
]
},
// Another sub document
{
_id: 6,
"org_name": "sony",
"items": [
{
"item_id": "10",
"data": [
// Values goes here
]
},
{
"item_id": "11",
"data": [
// Values goes here
]
}
]
}
Each sub document corresponds to individual organizations and each organization has an array of items in them.
What I need is to get the select individual elements from the items array, by providing item_id.
I already tried this:-
db.organizations.find({"_id": 5}, {items: {$elemMatch: {"item_id": {$in: ["10", "11"]}}}})
But it is returning either the item list with *item_id* "10" OR the item list with *item_id* "11".
What I need is is the get values for both item_id 10 and 11 for the organization "abc". Please help.

Answer 1

update2:
db.organizations.aggregate([
// you can remove this to return all your data
{$match:{_id:5}},
// unwind array of items
{$unwind:"$items"},
// filter out all items not in 10, 11
{$match:{"items.item_id":{"$in":["10", "11"]}}},
// aggregate again into array
{$group:{_id:"$_id", "items":{$push:"$items"}}}
])
update:
db.organizations.find({
"_id": 5,
items: {$elemMatch: {"item_id": {$in: ["10", "11"]}}}
})
old Looks like you need aggregation framework, particularly $unwind operator:
db.organizations.aggregate([
{$match:{_id:5}}, // you can remove this to return all your data
{$unwind:"$items"}
])