Querying a multi-nested array in MongoDb 3.4.2 - mongodb

Question

MongoDB Version - 3.4.2
I'm trying to query within the Sitecore Analytics database, trying to retrieve all users that are associated with a given List Id.
The example dataset I have follows the default Sitecore Analytics setup:
"Tags" : {
"Entries" : {
"ContactLists" : {
"Values" : {
"0" : {
"Value" : "{1E2D1AB7-72A0-4FF7-906B-DCDC020B87D2}",
"DateTime" : ISODate("2020-10-23T17:38:13.891Z")
},
"1" : {
"Value" : "{28BECCD3-476B-4B1D-9A75-02E59EF21286}",
"DateTime" : ISODate("2018-04-18T14:22:41.763Z")
},
"2" : {
"Value" : "{2C2BB0C3-483D-490E-B93A-9155BFBBE5DC}",
"DateTime" : ISODate("2018-05-10T14:26:08.494Z")
},
"3" : {
"Value" : "{DBE480F6-E305-4B35-9E6D-CBED64F4E44F}",
"DateTime" : ISODate("2018-10-27T02:41:28.776Z")
},
}
}
}
},
I want to iterate through all the entries within Values without having to specify 0/1/2/3, avoiding the following:
db.getCollection('Contacts').find({"Tags.Entries.ContactLists.Values.1.Value": "{28BECCD3-476B-4B1D-9A75-02E59EF21286}"})
I've tried the following:
db.getCollection('Contacts').find({"Tags.Entries.ContactLists.Values": {$elemMatch : {"Value":"{28BECCD3-476B-4B1D-9A75-02E59EF21286}"}}})
db.getCollection('Contacts').find({'Tags' : {$elemMatch : {$all : ['{28BECCD3-476B-4B1D-9A75-02E59EF21286}']}}})
db.getCollection('Contacts').forEach(function (doc) {
for(var i in doc.Tags.Entries.ContactLists.Values)
{
doc.Tags.Entries.ContactLists.Values[i].Value = "{28BECCD3-476B-4B1D-9A75-02E59EF21286}";
}
})
And a few other variations which I cannot recall now. And none work.
Any ideas if this is possible or on how to do this?
I want the outcome to just show filter out the results showing only the entries containing the matching GUID
Many thanks!

Answer 1

Demo - https://mongoplayground.net/p/upgYxgzPwJQ
It can be done using aggregation pipeline
Use $objectToArray to convert array
Use $filter to filter the array
db.collection.aggregate([
{
$addFields: {
filteredValue: {
$filter: {
input: {
$objectToArray: "$Tags.Entries.ContactLists.Values"
},
as: "val",
cond: {
$eq: [ // filter condition
"$$val.v.Value",
"{28BECCD3-476B-4B1D-9A75-02E59EF21286}"
]
}
}
}
}
}
])
Output -
[
{
"Tags": {
"Entries": {
"ContactLists": {
"Values": {
"0": {
"DateTime": ISODate("2020-10-23T17:38:13.891Z"),
"Value": "{1E2D1AB7-72A0-4FF7-906B-DCDC020B87D2}"
},
"1": {
"DateTime": ISODate("2018-04-18T14:22:41.763Z"),
"Value": "{28BECCD3-476B-4B1D-9A75-02E59EF21286}"
},
"2": {
"DateTime": ISODate("2018-05-10T14:26:08.494Z"),
"Value": "{2C2BB0C3-483D-490E-B93A-9155BFBBE5DC}"
},
"3": {
"DateTime": ISODate("2018-10-27T02:41:28.776Z"),
"Value": "{DBE480F6-E305-4B35-9E6D-CBED64F4E44F}"
}
}
}
}
},
"_id": ObjectId("5a934e000102030405000000"),
"filteredValue": [
{
"k": "1",
"v": {
"DateTime": ISODate("2018-04-18T14:22:41.763Z"),
"Value": "{28BECCD3-476B-4B1D-9A75-02E59EF21286}"
}
}
]
}
]

Answer 2

You can not use $elemMatch because Values is not array, but object. You can solve the problem with Aggregation Pipeline:
$addFields to add new field Values_Array that will be array representation of Values object.
$objectToArray to transform Values object to array
$match to find all documents that has requested value in new Values_Array field
$project to specify which properties to return from the result
db.getCollection('Contacts').aggregate([
{
"$addFields": {
"Values_Array": {
"$objectToArray": "$Tags.Entries.ContactLists.Values"
}
}
},
{
"$match": {
"Values_Array.v.Value": "{28BECCD3-476B-4B1D-9A75-02E59EF21286}"
}
},
{
"$project": {
"Tags": 1
}
}
])
Here is the working example: https://mongoplayground.net/p/2gY-vu3Qrvz