Extract value of array and add in the same select mongoDB - spring

Question

I am new to the mongoDB aggregation and I have this situation. I have this Json and I need to convert by "select" this object:
{
"type": "PF",
"code": 12345
"Name": Darth Vader,
"currency": "BRL",
"status": "SINGLE",
"adress": [
{
"localization": "DEATH STAR",
"createDate": 1627990848665
},
{
"localization": "TATOOINE",
"createDate": 1627990555665
},
]
}
this way:
{
"type": "PF",
"code": 12345
"Name": Darth Vader,
"currency": "BRL",
"status": "SINGLE",
"localization": "DEATH STAR",
"createDate": 1627990848665
},
{
"type": "PF",
"code": 12345
"Name": Darth Vader,
"currency": "BRL",
"status": "SINGLE",
"localization": "TATOOINE",
"createDate": 1627990555665
}
So, after my query is complete, I will have 02 objects instead of 01. How can I do this?
I would like to do this via select because after converting I will sort by createDate and limit the number of records to return to the API. I'm using Criteria em my project.

Answer 1

The way to do this is $unwind, this will make 1 copy of the document, for each member of the array.
Test code here
db.collection.aggregate([
{
"$unwind": {
"path": "$user.adress"
}
},
{
"$set": {
"user": {
"$mergeObjects": [
"$user",
"$user.adress"
]
}
}
},
{
"$unset": [
"user.adress"
]
},
{
"$sort": {
"createDate": 1
}
},
{
"$limit": 10
}
])
Edit1 (the above is if user is a field, if it was the name of the collection)
$$ROOT is a system variable that has as value all the document
Test code here
Query
db.collection.aggregate([
{
"$unwind": {
"path": "$adress"
}
},
{
"$replaceRoot": {
"newRoot": {
"$mergeObjects": [
"$$ROOT",
"$adress"
]
}
}
},
{
"$unset": [
"adress"
]
},
{
"$sort": {
"createDate": 1
}
},
{
"$limit": 10
}
])