Push values in Mongo Nested Array - mongodb

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Let's say that we have many documents like this in the photo
I have the above schema. I want to find the document based on _id first and then push an array of values to providedServices which belongs to the _id which is inside barbers array
A little help. Can't seem to find this out!

You need to find the related arrays firstly. For this, you can use $elemMatch or write it as 'barbers._id' : {$elemMatch: parameter}' .
Here we tried to find document with filtering it's own id and barbers id. You can change the filter as you wished. It can be only search on barbers id.
Need to write your DocumentName and your parameters instead of idValue, barbersId, serviceModel.
const result = await DocumentName.findOneAndUpdate(
{
$and:
[
{_id: mongoose.Types.ObjectId(idValue)},
{'barbers': {$elemMatch: {_id: mongoose.Types.ObjectId(barbersId)}}}
]
},
{ $push: { 'barbers.$.providedServices': serviceModel } },
{ new: true })
At first, we found the related barbers array inside of all documents. Then we pushed the model inside of providedServices array into this barbers array.

Related

MongoDB : Match with element in an array

I am working on a collection called Publications. Each publication has an array of objectives which are ids. I have also a custom array of objectives hand written. Now, I want to select all the publications that contains at least one element of the custom objectives array in their objectives. How can I do that ?
I've been trying to make this works with '$setIntersection' then '$count' and verify that the count is greater than 0 but I don't know how to implement this.
Example :
publication_1: {
'_id': ObjectId("sdfsdf46543")
'objectives': [ObjectId("1654351456341"), ObjectId("123456789")]
}
publication_2: {
'_id': ObjectId("sdfs216546543")
'objectives': [ObjectId("1654351456341"), ObjectId("46531132")]
}
custom_array = [ObjectId("123456789"), ObjectId("2416315463")]
The mongo query should return publication_1.
You can do like the following:
db.publications.find({
"objectives": {
"$in": [
ObjectId("123456789"),
ObjectId("2416315463")
]
}
})
Notice: "123456789" is not a valid ObjectId so the query itself may not work. Here is the working example
Mongodb playground link: https://mongoplayground.net/p/MbZK99Pd5YR
objectives is an array of objects, I guess you can just query that field directly:
let custom_array = [ObjectId("123456789"), ObjectId("2416315463")];
// You can search the array with $in property.
let result = await Model.find({ objectives: {$in : custom_array} })

Mongoose findOneAndUpdate an array within an array within a document

I'm trying to update an array that sits inside another array in a document. The schema is like this:
const projectSchema = new mongoose.Schema({
stakeholders: [{
stakeholderTitle: {
type: String,
},
...
subgroup: [{
subgroupTitle: {
type: String
},
subgroupPercent: {
type: Number,
}
}]
}],
and I'm trying to update the 'subgroup' array. I have got the query to work on its parent (the stakeholder array) with the positional $ operator, using the answer to this question I asked previously. So my query looks like this.....
await db.findOneAndUpdate({ find by the id }, { "stakeholders.$.stakeholderTitle": req.body.stakeholderTitle, ... "stakeholders.$.subgroup": req.body.subgroup })
However, this query doesn't work for the 'stakeholders subgroup' array, and makes it null. Looking through the mongo docs for the positional operator it states that 'The positional $ operator cannot be used for queries which traverse more than one array, such as queries that traverse arrays nested within other arrays, because the replacement for the $ placeholder is a single value', which I guess might be my problem.
So how can I do this with a findOneAndUpdate query?
From what I see is you have to specify the object you want to update inside the subgroup array. Try this - (i.e I'm updating the subgroupTitle of the subgroup array);
await db.findOneAndUpdate(
{
_id: userId,
"stakeholders.stakeholderTitle": req.body.stakeholderTitle,
"stakeholders.stakeholderTitle.subgroup.subgroupTitle": req.body.subgroupTitle
},
{$set: {
"stakeholders.stakeholderTitle.subgroup.$.subgroupPercent": somePercentValue,
}
},
);
Also note, it's only the array that you find that you can update. It might not be exactly what you want, but its a step closer

Mongoose Updating an array in multiple documents by passing an array of filters to update query

I have multiple documents(3 documents in this example) in one collection that looks like this:
{
_id:123,
bizs:[{_id:'',name:'a'},{_id:'',name:'b'}]
},
{
_id:456,
bizs:[{_id:'',name:'e'},{_id:'',name:'f'}]
}
{
_id:789,
bizs:[{_id:'',name:'x'},{_id:'',name:'y'}]
}
Now, I want to update the bizs subdocument by matching with my array of ids.
That is to say, my array filter for update query is [123,789], which will match against the _id fields of each document.
I have tried using findByIdAndUpdate() but that doesn't allow an array for the update query
How can I update the 2 matching documents (like my example above) without having to put findByIdAndUpdate inside a forloop to match the array element with the _id?
You can not use findByIdAndUpdate when updating multiple documents, findByIdAndUpdate is from mongoose which is a wrapper to native MongoDB's findOneAndUpdate. When you pass a single string as a filter to findByIdAndUpdate like : Collection.findByIdAndUpdate({'5e179dac627ef7823643cd97'}, {}) - then mongoose will internally convert string to ObjectId() & form it as a filter like :_id : ObjectId('5e179dac627ef7823643cd97') to execute findOneAndUpdate. So it means you can only update one document at a time, So if you've multiple documents to be updated use update with option {multi : true} or updateMany.
Assume if you wanted to push a new object to bizs, this is how query looks like :
collection.updateMany({ _id: { $in: [123, 456] } }, {
$push: {
bizs: {
"_id": "",
"name": "new"
}
}
})
Note : Update operations doesn't return the documents in response rather they will return write result which has information about n docs matched & n docs modified.

MongoDB new ObjectId over array giving me same Id for all

I am trying to update items in an array with unique ObjectIds (meaning add an object ID to array object that are missing them)
If I have an array of shirt objects in my collection and I try this:
db.people.update({
$and : [
_id: ObjectId('5eeb44c6a042791d28a8641f'),
{
$or: [
{ 'shirts._id': { $eq:null } },
{ 'shirts._id':{ $exists:false } }
]
}
]
},{
$set: { 'shirts.$[]._id': new ObjectId() }
},{
"multi" : true
}
);
It generates IDENTICAL ObjectsIDs for each array element, I would put an unique index on this however, the use case probably wont see more then 2-3 items in the array with edge cases hitting 5-6, which seems like an abuse of an index
How can I update multiple records or multiple array objects with a unique ObjectId?
When you use $set you're telling mongo to set that value to all matching elements. If the elements in the array are already defined as schemas, mongo will issue new ObjectIds for each one of them automatically.
Alternatively, you can use forEach and iterate over each matching element creating a new ObjectId.

How to fetch just the "_id" field from MongoDB find()

I wish to return just the document id's from mongo that match a find() query.
I know I can pass an object to exclude or include in the result set, however I cannot find a way to just return the _id field.
My thought process is returning just this bit of information is going to be way more efficient (my use case requires no other document data just the ObjectId).
An example query that I expected to work was:
collection.find({}, { _id: 1 }).toArray(function(err, docs) {
...
}
However this returns the entire document and not just the _id field.
You just need to use a projection to find what ya want.
collection.find({filter criteria here}, {foo: 0, bar: 0, _id: 1});
Since I don't know what your document collection looks like this is all I can do for you. foo: 0 for example is exclude this property.
I found that using the cursor object directly I can specify the required projection. The mongodb package on npm when calling toArray() is returning the entire document regardless of the projection specified in the initial find(). Fixed working example below that satisfies my requirements of just getting the _id field.
Example document:
{
_id: new ObjectId(...),
test1: "hello",
test2: "world!"
}
Working Projection
var cursor = collection.find({});
cursor.project({
test1: 0,
test2: 0
});
cursor.toArray(function(err, docs) {
// Importantly the docs objects here only
// have the field _id
});
Because _id is by definition unique, you can use distinct to get an array of the _id values of all documents as:
collection.distinct('_id', function(err, ids) {
...
}
you can do like this
collection.find({},'_id').toArray(function(err, docs) {
...
}