MongoDB Query to Convert String to Int

To convert string to int, use parseInt() in MongoDB. Let us first create a collection with documents −

> db.demo369.insertOne({"Price":"1000000"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e57e2e32ae06a1609a00aed")
}
> db.demo369.insertOne({"Price":"1747864"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e57e2e92ae06a1609a00aee")
}
> db.demo369.insertOne({"Price":"19548575"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e57e2ee2ae06a1609a00aef")
}

Display all documents from a collection with the help of find() method −

> db.demo369.find();

This will produce the following output −

{ "_id" : ObjectId("5e57e2e32ae06a1609a00aed"), "Price" : "1000000" }
{ "_id" : ObjectId("5e57e2e92ae06a1609a00aee"), "Price" : "1747864" }
{ "_id" : ObjectId("5e57e2ee2ae06a1609a00aef"), "Price" : "19548575" }

Following is the query to convert string to int −

> db.demo369.find().forEach( function (d) {
...    d.Price= parseInt(d.Price);
...    db.demo369.save(d);
... });

Display all documents from a collection with the help of find() method −

> db.demo369.find();

This will produce the following output −

{ "_id" : ObjectId("5e57e2e32ae06a1609a00aed"), "Price" : 1000000 }
{ "_id" : ObjectId("5e57e2e92ae06a1609a00aee"), "Price" : 1747864 }
{ "_id" : ObjectId("5e57e2ee2ae06a1609a00aef"), "Price" : 19548575 }