Increment a field in MongoDB document which is embedded?

Let’s say, here we are incrementing StudentScores for MongoDB which is inside StudentDetails −

... "StudentScores": { ...    "StudentMathScore": 90, ...    "StudentMongoDBScore": 78 ... }

Let us first create a collection with documents −

> db.embeddedValueIncrementDemo.insertOne( ...    { ...       "StudentDetails": { ...          "StudentScores": { ...             "StudentMathScore": 90, ...             "StudentMongoDBScore": 78 ...          } ...       } ...    } ... ); {    "acknowledged" : true,    "insertedId" : ObjectId("5cd2b670345990cee87fd896") }

Following is the query to display all documents from a collection with the help of find() method −

> db.embeddedValueIncrementDemo.find().pretty();

This will produce the following output −

{    "_id" : ObjectId("5cd2b670345990cee87fd896"),    "StudentDetails" : {       "StudentScores" : {          "StudentMathScore" : 90,          "StudentMongoDBScore" : 78       }    } }

Following is the query to increment embedded value. Here, we are incrementing StudentMongoDBScore −

> db.embeddedValueIncrementDemo.update({ _id: new ObjectId("5cd2b670345990cee87fd896") }, { $inc: { "StudentDetails.StudentScores.StudentMongoDBScore": 20 } }, { upsert: true, safe: true }, null); WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })

Let us check all the documents once again −

> db.embeddedValueIncrementDemo.find().pretty();

This will produce the following output −

{    "_id" : ObjectId("5cd2b670345990cee87fd896"),    "StudentDetails" : {       "StudentScores" : {          "StudentMathScore" : 90,          "StudentMongoDBScore" : 98       }    } }