How to create a user in MongoDB v3?

To create a user in MongoDB v3, use the createUser() method. This allows you to create a user and while creating you need to add user, password, and roles as well. These roles assign permissions. The syntax is as follows −

use admin
db.createUser(
   {
      user: “yourUserName",
      pwd: "yourPassword",
      roles: [ { role: "yourPermission", db: "yourDatabase" } ]
   }
);

Let us implement the above syntax in order to create a user In MongoDB v3 −

> use admin
switched to db admin
> db.createUser(
...    {
...       user: "Robert",
...       pwd: "robert",
...       roles: [ { role: "readWrite", db: "sample" } ]
...    }
... );

Above, we have set the following for the new user −

User: Robert
Password: robert
Roles: readWrite
This will produce the following output:
Successfully added user: {
   "user" : "Robert",
   "roles" : [
      {
         "role" : "readWrite",
         "db" : "sample"
      }
   ]
}

We have successfully created a new user “Robert” above.