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Mongodb findOneAndUpdate - check if new document added, or just updated

I have the following code which is finding and updating an employee-store record (if it exists, otherwise it creates one).
I have lots of employees in different stores, and they can choose to change store at any point (as long as the location is in America)
Below is my code so far:
employee = await this.employeeStoreModel.findOneAndUpdate(
{ employee: employeeRecord._id, location: "America" },
{
employee: employeeRecord._id,
store: employeeRecord.store,
location: "America",
},
{ new: true, upsert: true }
);
This works correctly, however I am trying to return some messages from this based on what is being updated. It could be any of the following messages:
If it's a completely new employee-store record being added, then return "{{StoreID}} has a new employee - {{EmployeeID}}"
If it's a change of store on an existing employee-store record, then return "{{EmployeeID}} has changed from {{old StoreID}} to {{new StoreID}}"
Is this possible to do? Can anyone guide me on how I could start this?

In the Options field,
rawResult: true
You must add the parameter.
The result will be as in the example below.
{ response:
{ n: 1,
updatedExisting: false,
upserted: 5e6a9e5ec6e44398ae2ac16a },
value:
{ _id: 5e6a9e5ec6e44398ae2ac16a,
name: 'Will Riker',
__v: 0,
age: 29 },
ok: 1 }
Depending on whether there is an update or insert in the updatedExisting field, you can return any message you want.

Model.updateOne() correct syntax [duplicate]

Consider I have this document in my MongoDB collection, Workout:
{
_id: ObjectId("60383b491e2a11272c845749") <--- Workout ID
user: ObjectId("5fc7d6b9bbd9473a24d3ab3e") <--- User ID
exercises: [
{
_id: ObjectId("...") <--- Exercise ID
exerciseName: "Bench Press",
sets: [
{
_id: ObjectId("...") <--- Set ID
},
{
_id: ObjectId("...") <--- Set ID
}
]
}
]
}
The Workout object can include many exercise objects in the exercises array and each exercise object can have many set objects in the sets array. I am trying to implement a delete functionality for a certain set. I need to retrieve the workout that the set I want to delete is stored in. I have access to the user's ID (stored in a context), exercise ID and the set ID that I want to delete as parameters for the .findOne() function. However, I'm not sure whether I can traverse through the different levels of arrays and objects within the workout object. This is what I have tried:
const user = checkAuth(context) // Gets logged in user details (id, username)
const exerciseID, setID // Both of these are passed in already and are set to the appropriate values
const workoutLog = Workout.findOne({
user: user.id,
exercises: { _id: exerciseID }
});
This returns an empty array but I am expecting the whole Workout object that contains the set that I want to delete. I would like to omit the exerciseID from this function's parameters and just use the setID but I'm not sure how to traverse through the array of objects to access it's value. Is this possible or should I be going about this another way? Thanks.

When matching against an array, if you specify the query like this:
{ exercises: { _id: exerciseID } }
MongoDB tries to do an exact match on the document. So in this case, MongoDB would only match documents in the exercises array of the exact form { _id: ObjectId("...") }. Because documents in the exercises have other fields, this will never produce a match, even if the _ids are the same.
What you want to do instead is query a field of the documents in the array. The complete query document would then look like this:
{
user: user.id,
"exercises._id": exerciseID
}

You can perform both find and update in one step. Try this:
db.Workout.updateOne(
{
"user": ObjectId("5fc7d6b9bbd9473a24d3ab3e"),
},
{
$pull: {
"exercises.$[exercise].sets": {
"_id": ObjectId("6039709fe0c7d52970d3fa30") // <--- Set ID
}
}
},
{
arrayFilters: [
{
"exercise._id" : ObjectId("6039709fe0c7d52970d3fa2e") // <--- Exercise ID
}
]
}
);

How to filter only some rows of an array inside a document?

I have a MongoDB collection of documents, using a schema like this:
var schema = new Schema({
name: String,
images: [{
uri: string,
active: Boolean
}]
});
I'd like to get all documents (or filter using some criteria), but retrieve - in the images array - only the items with a specific property (in my case, it's {active: true}).
This is what I do now:
db.people.find( { 'images.active': true } )
But this retrieves only documents with at least one image which is active, which is not what I need.
I know of course I can filter in code after the find is returned, but I do not like wasting memory.
Is there a way I can filter array items in a document using mongoose?

Here is the aggregation you're looking for:
db.collection.aggregate([
{
$match: {}
},
{
$project: {
name: true,
images: {
$filter: {
input: "$images",
as: "images",
cond: {
$eq: [
"$$images.active",
true
]
}
}
}
}
}
])
https://mongoplayground.net/p/t_VxjfiBBMK

What is the best way to keep track of changes of a document's property in MongoDB?

I would like to know how to keep track of the values of a document in MongoDB.
It's a MongoDB Database with a Node and Express backend.
Say I have a document, which is part of the Patients collection.
{
"_id": "4k2lK49938d82kL",
"firstName": "John",
"objective": "Burn fat"
}
Then I edit the "objective" property, so the document results like this:
{
"_id": "4k2lK49938d82kL",
"firstName": "John",
"objective": "Gain muscle"
}
What's the best/most efficient way to keep track of that change? In other words, I would like to know that the "objective" property had the value "Burn fat" in the past, and access it in the future.
Thanks a lot!

Maintaining/tracking history in the same document is not all recommended. As the document size will keep on increasing leading to
probably if there are too many updates, 16mb document size limit
Performance degrades
Instead, you should maintain a separate collection for history. You might have use hibernates' Javers or envers for auditing for your relational databases. if not you can check how they work. A separate table (xyz_AUD) is maintained for each table (xyz). For each row (with primary key abc) in xyz table, there exist multiple rows in xyz_AUD table, where each row is version of that row.
Moreover, Javers also support MongoDB auditing. If you are using java you can directly use it. No need to write your own logic.
Refer - https://nullbeans.com/auditing-using-spring-boot-mongodb-and-javers/
One more thing, Javers Envers Hibernate are java libraries. But I'm sure for other programming languages also, similar libraries will be present.
There is a mongoose plugin as well -
https://www.npmjs.com/package/mongoose-audit (quite oudated 4 years)
https://github.com/nassor/mongoose-history#readme (better)

Maybe you can change the type of "objective" to array and track the changes in it. the last one of the array is the latest value.

Maintain it as a sub-document like below
{
"_id": "4k2lK49938d82kL",
"firstName": "John",
"objective": {
obj1: "Gain muscle",
obj2: "Burn fat"
}
}
You can also maintain it as an array field but remember, mongodb doesn't allow you to maintain uniqueness in an array field and if you plan to index the "objective" field, you'll have to create a multi key index

I think the simplest solution would be to use and update an array:
const patientSchema = new Schema({
firstName: { type: String, required: true },
lastName: { type: String, required: true },
objective: { type: String, required: true }
notes: [{
date: { type: Date, default: Date.now() },
note: { type: String, required: true }
}],
});
Then when you want to update the objective...
const updatePatientObjective = async (req, res) => {
try {
// check if _id and new objective exist in req.body
const { _id, objective, date } = req.body;
if (!_id || !objective) throw "Unable to update patient's objective.";
// make sure provided _id is valid
const existingPatient = await Patient.findOne({ _id });
if (!existingPatient) throw "Unable to locate that patient.";
// pull out objective as previousObjective
const { objective: previousObjective } = existingPatient;
// update patient's objective while pushing
// the previous objective into the notes sub document
await existingPatient.updateOne({
// update current objective
$set { objective },
// push an object with a date and note (previouseObjective)
// into a notes array
$push: {
notes: {
date,
note: previousObjective
},
},
}),
);
// send back response
res
.status(201)
.json({ message: "Successfully updated your objective!" });
} catch (err) {
return res.status(400).json({ err: err.toString() });
}
};
Document will look like:
firstName: "John",
lastName: "Smith",
objective: "Lose body fat.",
notes: [
{
date: 2019-07-19T17:45:43-07:00,
note: "Gain muscle".
},
{
date: 2019-08-09T12:00:38-07:00,
note: "Work on cardio."
}
{
date: 2019-08-29T19:00:38-07:00,
note: "Become a fullstack web developer."
}
...etc
]
Alternatively, if you're worried about document size, then create a separate schema for patient history and reference the user's id (or just store the patient's _id as a string instead of referencing an ObjectId, whichever you prefer):
const patientHistorySchema = new Schema({
_id: { type: Schema.Types.ObjectId, ref: "Patient", required: true },
objective: { type: String, required: true }
});
Then create a new patient history document when the objective is updated...
PatientHistory.create({ _id, objective: previousObjective });
And if you need to access to the patient history documents...
PatientHistory.find({ _id });

Update an array of objects mongoose

I know that this question might be beginner level but I haven't find anything yet.
I would like to update an array of objects with mongoose. I am interested in updating one object from the users array according to the index.
Usually one user is getting changed at a time.
Here is my schema:
_id: Schema.Types.ObjectId,
name: { type: String, required: true },
gm: {
type: Schema.Types.ObjectId,
ref: 'User',
required: true
},
users: [],
I want to update an object in the users array which is like this:
{
id:"5bcb7c7ff9c5c01b9482d244",
gm:"5bcb7c7ff9c5c01b9482d246",
name:"room 1"
users: [
{
id:"5bcb7c7ff9c5c01b9482d243",
stats:{
power:10,
mobility: 5,
vitality: 20
},
bag:{itemSlot1: "Knife",itemSlot2:"Sword" }
},
{
id:"5bcb7c7ff9c5c01b9482d241",
stats:{
power:10,
mobility: 5,
vitality: 20
},
bag:{itemSlot1: "Knife",itemSlot2:"Sword" }
]
}
I want to perform a patch or a post request to update one user each time from the user array. i am getting the id of the user from req.body to match it with my db.
My request is like this:
I would like to update based on a request like this:
data = {
stats={
power:"10",
vitality:"20"
}
}
Thanks in advance,
Cheers

You can do an update like this:
YourSchema.update({
'users.id': '5bcb7c7ff9c5c01b9482d243'
}, {
$set: {
'users.$.stats': data.stats
}
})
Which would update the first user with id 5bcb7c7ff9c5c01b9482d243 power stats to 20
This is using the update with the $ positional operator to update the element in the array.
Just have it set up in your post/patch request.