Performing a single database call to insert multiple subdocuments at once

Question

Performing a single database call to insert multiple subdocuments at once

If I have a document containing an array of objects.

Data = {
  _id: 1,
  total_amount: 0,
  subDataArray: [
  {      
   _id: 1,
   amount: 0   
  },
  {      
   _id: 2,
   amount: 1   
  },
  ...
 ]
}

Updating the total_amount can be done simply like this...

Data.updateOne({ _id }, { $inc: { total_amount: 1} })

However, incrementing the amounts in subDataArray is more complex. If I have an array of updates for Data.subDataArray

var newSubDataArray = [
  {      
   _id: 1,
   amount: 5   
  },
  {      
   _id: 2,
   amount: 5   
  },
]

Is there a way to increment all amounts in Data.subDataArray with just one operation? Keep in mind that newSubDataArray may not always contain every item present in subDataArray, so it would require upsert behavior.

Can this even be achieved?

EDIT: Just to clarify, each amount value in newSubDataArray could differ from one another. The goal is to increment each existing subDataArray item's amount by the respective value found in newSubDataArray based on matching IDs.

javascript mongodb mongoose

Answer 1

Answer №1

Since my previous response did not fully address the question, here is a revised explanation.

In MongoDB, it is not possible to update multiple array elements in one call; you need to make individual calls for each new array element. You can utilize arrayFilters to update all items that match the current element. Below is an example showcasing different behaviors:

Original document:

{ 
    "_id" : 1.0, 
    "doc_amount" : 0.0, 
    "subDocsArray" : [
        {
            "_id" : 1.0, 
            "amount" : 20.0
        }, 
        {
            "_id" : 2.0, 
            "amount" : 31.0
        }, 
        {
            "_id" : 3.0, 
            "amount" : 3.0
        }, 
        {
            "_id" : 5.0
        }
    ]
}

Applying the below script:

var newSubDocsArray = [
  {      
   _id: 1,
   amount: 3  
  },
  {      
   _id: 2,
   amount: 8   
  },
    {      
   _id: 4,
   amount: 7   
  },
      {      
   _id: 5,
   amount: 9   
  },
];


newSubDocsArray.forEach(function(newSubDoc){
  db.getCollection("test").update(
    {_id:1},   
    {$inc:{"subDocsArray.$[subdoc].amount":newSubDoc.amount}},   // Note the use of $[subdoc]
    { multi: true,
       arrayFilters: [ { "subdoc._id": newSubDoc._id } ]
    }
  )
})

This script will result in:

{ 
    "_id" : 1.0, 
    "doc_amount" : 0.0, 
    "subDocsArray" : [
        {
            "_id" : 1.0, 
            "amount" : 23.0   // +3
        }, 
        {
            "_id" : 2.0, 
            "amount" : 39.0   // +8
        }, 
        {
            "_id" : 3.0, 
            "amount" : 3.0    // unchanged
        }, 
        {
            "_id" : 5.0, 
            "amount" : 9.0    // created and set to 9
        }
    ]
}

Key points to note:

The item with _id 3 remains unchanged as it is not present in the newSubDocsArray.
The item with _id 4 is not created in the array as the arrayFilters do not find a matching element.
The items with _id 5 have a new amount field created.

Answer 2

Since my previous response did not fully address the question, here is a revised explanation.

In MongoDB, it is not possible to update multiple array elements in one call; you need to make individual calls for each new array element. You can utilize arrayFilters to update all items that match the current element. Below is an example showcasing different behaviors:

Original document:

{ 
    "_id" : 1.0, 
    "doc_amount" : 0.0, 
    "subDocsArray" : [
        {
            "_id" : 1.0, 
            "amount" : 20.0
        }, 
        {
            "_id" : 2.0, 
            "amount" : 31.0
        }, 
        {
            "_id" : 3.0, 
            "amount" : 3.0
        }, 
        {
            "_id" : 5.0
        }
    ]
}

Applying the below script:

var newSubDocsArray = [
  {      
   _id: 1,
   amount: 3  
  },
  {      
   _id: 2,
   amount: 8   
  },
    {      
   _id: 4,
   amount: 7   
  },
      {      
   _id: 5,
   amount: 9   
  },
];


newSubDocsArray.forEach(function(newSubDoc){
  db.getCollection("test").update(
    {_id:1},   
    {$inc:{"subDocsArray.$[subdoc].amount":newSubDoc.amount}},   // Note the use of $[subdoc]
    { multi: true,
       arrayFilters: [ { "subdoc._id": newSubDoc._id } ]
    }
  )
})

This script will result in:

{ 
    "_id" : 1.0, 
    "doc_amount" : 0.0, 
    "subDocsArray" : [
        {
            "_id" : 1.0, 
            "amount" : 23.0   // +3
        }, 
        {
            "_id" : 2.0, 
            "amount" : 39.0   // +8
        }, 
        {
            "_id" : 3.0, 
            "amount" : 3.0    // unchanged
        }, 
        {
            "_id" : 5.0, 
            "amount" : 9.0    // created and set to 9
        }
    ]
}

Key points to note:

The item with _id 3 remains unchanged as it is not present in the newSubDocsArray.
The item with _id 4 is not created in the array as the arrayFilters do not find a matching element.
The items with _id 5 have a new amount field created.

Answer 3

Answer №2

One way to accomplish this is by using the $[] array update operator:

db.getCollection("test").update(
  {_id:1},   
  {$inc:{"subDocsArray.$[].amount":1}}
)

Answer 4

One way to accomplish this is by using the $[] array update operator:

db.getCollection("test").update(
  {_id:1},   
  {$inc:{"subDocsArray.$[].amount":1}}
)

Answer 5

Answer №3

To modify a specific sub-array element in MongoDB, you can use the following syntax:

Start by specifying the criteria: { _id: 1,'subDocsArray._id' : 1}

Then update the item using: {$inc :{'subDocsArray.$.amount':1}}

Answer 6

To modify a specific sub-array element in MongoDB, you can use the following syntax:

Start by specifying the criteria: { _id: 1,'subDocsArray._id' : 1}

Then update the item using: {$inc :{'subDocsArray.$.amount':1}}

Performing a single database call to insert multiple subdocuments at once

Answer №1

Answer №2

Answer №3

Similar questions

Text in Angular vanishes upon reopening

Struggling to insert HTML into an element using JavaScript or jQuery within a function

Injecting dynamic content using JavaScript

The Ionic2 http post request is missing the 'Access-Control-Allow-Origin' header

Upon running `npm start`, an unexpected token error arises in the file originating from a local

Issues with Mega Menu functionality preventing items from being clickable and links from properly navigating

What is the best way to incorporate ajax into a Wordpress theme?

Load HTML content without having to refresh the page

How can I show or hide all child elements of a DOM node using JavaScript?

Obtaining data from an ajax request in node.js

Learn how to incorporate a conditional $match condition in MongoDB

Adding new fields to existing documents in MongoDB

Leveraging Angular 4 component as a custom widget within a static website

Remove a particular file from the collection

Element on webpage "Expands" When Scrolled into Visibility

Exploring Angular 10: Managing Two Promises in ngOnInit

Disable infinite scrolling when a checkbox is clicked

What is causing the unexpected behavior of deferred.resolve in the q manual?

Exploring Grunt (node): Ways to Display Available Tasks

Troubleshooting CodeIgniter's AJAX call functionality issue