how to sort an array in a nested array which is located under an object in mongodb - mongodb

Question

I have a collection data like below.
{
"name": "Devices",
"exten": {
"parameters": [{
"name": "Date",
"value": ["5","2"]
}, {
"name": "Time",
"value": ["2"]
}, {
"name": "Season",
"value": ["6"]
}
]
}
}
I want to take all data which is name "Devices" and sort by first index of "Value" which is parameter name is "Date"
ex: mongo will get
name = "devices"
exten.parameters.name = "Date"
will sort it by
exten.parameters.value[0]
in this example it will be sorted by "5".
below query returns 0 record.
db.brand.aggregate(
{ $match: {
"name" : "Devices"
}},
{ $unwind: "$exten.parameters" },
{ $match: {
'exten.parameters.name': 'Date'
}},
{ $sort: {
'exten.parameters.value': -1
}}
)

Answer 1

The following query can get us the expected output:
db.collection.aggregate([
{
$match:{
"name":"Devices"
}
},
{
$unwind:"$exten.parameters"
},
{
$match:{
"exten.parameters.name":"Date"
}
},
{
$project:{
"name":1,
"exten":1,
"firstParam":{
$arrayElemAt:["$exten.parameters.value",0]
}
}
},
{
$sort:{
"firstParam":1
}
},
{
$project:{
"firstParam":0
}
}
]).pretty()
Data set:
{
"_id" : ObjectId("5da02fb86472ba670fd8c159"),
"name" : "Devices",
"exten" : {
"parameters" : [
{
"name" : "Date",
"value" : [
"5",
"2"
]
},
{
"name" : "Date",
"value" : [
"2",
"7"
]
},
{
"name" : "Time",
"value" : [
"2"
]
},
{
"name" : "Season",
"value" : [
"6"
]
}
]
}
}
Output:
{
"_id" : ObjectId("5da02fb86472ba670fd8c159"),
"name" : "Devices",
"exten" : {
"parameters" : {
"name" : "Date",
"value" : [
"2",
"7"
]
}
}
}
{
"_id" : ObjectId("5da02fb86472ba670fd8c159"),
"name" : "Devices",
"exten" : {
"parameters" : {
"name" : "Date",
"value" : [
"5",
"2"
]
}
}
}