How to select specific columns in MongoDB query?

To select specific columns, you can ignore the rest of them i.e. to hide those columns, set them to 0. Let us first create a collection with documents −

> db.demo415.insertOne({"ClientName":"Robert","ClientCountryName":"US"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e72329db912067e57771adc")
}
> db.demo415.insertOne({"ClientName":"David","ClientCountryName":"UK"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e7232acb912067e57771add")
}
> db.demo415.insertOne({"ClientName":"Bob","ClientCountryName":"AUS"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e7232b4b912067e57771ade")
}

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

> db.demo415.find();

This will produce the following output −

{ "_id" : ObjectId("5e72329db912067e57771adc"), "ClientName" : "Robert", "ClientCountryName" : "US" }
{ "_id" : ObjectId("5e7232acb912067e57771add"), "ClientName" : "David", "ClientCountryName" : "UK" }
{ "_id" : ObjectId("5e7232b4b912067e57771ade"), "ClientName" : "Bob", "ClientCountryName" : "AUS" }

Following is the query to select specific columns. Here, we have ignored rest of the columns to display the column “ClientCountryName” −

> db.demo415.find({},{_id:0,ClientName:0});

This will produce the following output −

{ "ClientCountryName" : "US" }
{ "ClientCountryName" : "UK" }
{ "ClientCountryName" : "AUS" }