Can I retrieve multiple documents from MongoDB by id?

Yes, to retrieve multiple docs from MongoDB by id, use the $in operator. The syntax is as follows

db.yourCollectionName.find({_id:{$in:[yourValue1,yourValue2,yourValue3,...N]}});

Let us first create a collection with documents:

> db.retrieveMultipleDocsByIdDemo.insertOne({"_id":10,"CustomerName":"John"}); { "acknowledged" : true, "insertedId" : 10 } > db.retrieveMultipleDocsByIdDemo.insertOne({"_id":14,"CustomerName":"Chris"}); { "acknowledged" : true, "insertedId" : 14 } > db.retrieveMultipleDocsByIdDemo.insertOne({"_id":20,"CustomerName":"Robert"}); { "acknowledged" : true, "insertedId" : 20 } > db.retrieveMultipleDocsByIdDemo.insertOne({"_id":25,"CustomerName":"Sam"}); { "acknowledged" : true, "insertedId" : 25 } > db.retrieveMultipleDocsByIdDemo.insertOne({"_id":30,"CustomerName":"Bob"}); { "acknowledged" : true, "insertedId" : 30 } > db.retrieveMultipleDocsByIdDemo.insertOne({"_id":34,"CustomerName":"Carol"}); { "acknowledged" : true, "insertedId" : 34 }

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

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

This will produce the following output

{ "_id" : 10, "CustomerName" : "John" } { "_id" : 14, "CustomerName" : "Chris" } { "_id" : 20, "CustomerName" : "Robert" } { "_id" : 25, "CustomerName" : "Sam" } { "_id" : 30, "CustomerName" : "Bob" } { "_id" : 34, "CustomerName" : "Carol" }

Following is the query to retrieve multiple documents from MongoDB by id

> db.retrieveMultipleDocsByIdDemo.find({_id:{$in:[10,20,30]}});

This will produce the following output

{ "_id" : 10, "CustomerName" : "John" } { "_id" : 20, "CustomerName" : "Robert" } { "_id" : 30, "CustomerName" : "Bob" }