Fetch multiple documents in MongoDB query with OR condition?

Let us create a collection with documents −

> db.demo362.insertOne({"ClientName":"John","ClientProject":"School Management System"}); {    "acknowledged" : true,    "insertedId" : ObjectId("5e56a77454a481fef8ec7a1c") } > db.demo362.insertOne({"ClientName":"David","ClientProject":"Library Management System"}); {    "acknowledged" : true,    "insertedId" : ObjectId("5e56a78454a481fef8ec7a1d") } > db.demo362.insertOne({"ClientName":"Mike","ClientProject":"Event Tracker"}); {    "acknowledged" : true,    "insertedId" : ObjectId("5e56a7a054a481fef8ec7a1e") } > db.demo362.insertOne({"ClientName":"Carol","ClientProject":"Hospital Management System"}); {    "acknowledged" : true,    "insertedId" : ObjectId("5e56a7b754a481fef8ec7a1f") }

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

> db.demo362.find();

This will produce the following output −

{ "_id" : ObjectId("5e56a77454a481fef8ec7a1c"), "ClientName" : "John", "ClientProject" : "School Management System" } { "_id" : ObjectId("5e56a78454a481fef8ec7a1d"), "ClientName" : "David", "ClientProject" : "Library Management System" } { "_id" : ObjectId("5e56a7a054a481fef8ec7a1e"), "ClientName" : "Mike", "ClientProject" : "Event Tracker" } { "_id" : ObjectId("5e56a7b754a481fef8ec7a1f"), "ClientName" : "Carol", "ClientProject" : "Hospital Management System" }

Following is the query to fetch multiple documents −

> db.demo362.find({$or: [{"ClientName":"John"}, {"ClientProject": "Event Tracker" }]});

This will produce the following output −

{ "_id" : ObjectId("5e56a77454a481fef8ec7a1c"), "ClientName" : "John", "ClientProject" : "School Management System" } { "_id" : ObjectId("5e56a7a054a481fef8ec7a1e"), "ClientName" : "Mike", "ClientProject" : "Event Tracker" }