MongoDB - Update/Insert the Array of object - node.js

Question

I've one collection i.e 'comments', Which contain two fields. Like below -
Comments -
{
_id: 'unique_string',
dataVar: [{
name: {
type: string
},
value: {
type: string
}
}]
}
You can assume the collection data is like below -
[
_id: 'xxxxxx',
user: 'robin',
dataVar: [{
name: 'abc',
value: 123
}, {
name: 'bcd',
value: 12345
}]
]
Now the problem is - (I'm using mongoose in nodeJS application)
- How to update and insert the data in 'dataVar' ?
- If data is no available then new document should be created.
Case 1.
If user send the post data like
{
_id: 'xxxxxx',
user: 'robin',
dataVar: [{name: 'abc', value: 12345}]
}
then after performing query, the above document (whose _id is 'xxxxxx') should be update like below -
{
_id: 'xxxxxx',
user: 'robin',
dataVar: [
{name: 'abc', value: 12345},
{name: 'bcd', value: 12345}
]
}
Case 2.
If data is not present then new document should be created.

Answer 1

To update record in mongodb, you can use like
comments.findOneAndUpdate({ _id: 'xxxxxx' }, { $push: { dataVar: {$each: [{name: 'abc', value: 123}, {name: 'def', value: 456}] } } })
You can use {upsert: true} option for creating field in collection if not exist.
For updating record, you have to use sub-schema inside your main schema. So that _id field is created in every object of array. So you can uniquely identify object to update inside array.
comments.findOneAndUpdate({ "dataVar._id": 'xxxxxx' }, { $set: { name: 'xyz', value: 789 } })
In this way, you can update object, which is inside array.
If you don't want to use _id, you have at-least one field which contains unique values. So that you can findOneAndUpdate that specific object inside array.