MongoDB update multiple rows in a single query

Question

I have a collection with the following document

{
   "_id" : 1,
   "item" : "item1",
   "stock" : 184
}
{
   "_id" : 2,
   "item" : "item2",
   "stock" : 330
}
{
   "_id" : 3,
   "item" : "item3",
   "stock" : 140
}

I want to update this collection like this using a single query.

{
   "_id" : 1,
   "item" : "item1",
   "stock" : 80
}
{
   "_id" : 2,
   "item" : "item2",
   "stock" : 60
}
{
   "_id" : 3,
   "item" : "item3",
   "stock" : 170
}

I can do it using forEach but I have to update thousands of records at once which will time consuming. So does MongoDB have this functionality?

Your help will be highly appreciated.

Answer 1

You can use a bulk operation in nodejs via Collection.initializeUnorderedBulkOp

var bulkOp = yourCollection.initializeUnorderedBulkOp();

bulkOp.find({ _id: 1 }).updateOne({ /* update document */ });
bulkOp.find({ _id: 2 }).updateOne({ /* update document */ });
// etc

bulkOp.execute();

You can build it however you need to and then have the database do it all at once.