schema({
    virtuals: {
        propertyName: 'Program Logic'
    }
});

npm install mongoose

node index.js

// Require the mongoose module 
const mongoose = require('mongoose'); 
  
// Path to our cloud DataBase 
const url = "mongodb://localhost:27017/GFG"
  
// Connecting to database 
mongoose.set('strictQuery', false); 
  
mongoose.connect(url) 
    .then((ans) => { 
        console.log("Connected Successful") 
    }) 
    .catch((err) => { 
        console.log("Error in the Connection") 
    }) 
  
// Calling Schema class 
const Schema = mongoose.Schema; 
  
// Creating Structure of the model 
const schema = new Schema({ 
    firstName: { 
        type: String, 
        require: true, 
    }, 
    lastName: { 
        type: String, 
        require: true, 
    } 
}, 
    { 
        virtuals: { 
            fullName: { 
                get() { 
                    return this.firstName + 
                    ' ' + this.lastName; 
                } 
            } 
        } 
    }); 
  
// Compile our model 
const Person = mongoose.model('Person', schema); 
  
// Create a model 
const person = new Person( 
    { firstName: 'Sam', lastName: 'Snehil' } 
); 
  
// Using the virtuals function 
console.log( 
    'FullName without concatenation: ', 
    person.firstName + ' ' + person.lastName); 
console.log( 
    'Full Name with virtuals: ' + person.fullName 
)

FullName without concatenation:  Sam Snehil
Full Name with virtuals: Sam Snehil
Connected Successful

// Require the mongoose module 
const mongoose = require('mongoose'); 
  
// Path to our cloud DataBase 
const url = "mongodb://localhost:27017/GFG"
  
// Connecting to database 
mongoose.set('strictQuery', false); 
  
mongoose.connect(url) 
    .then((ans) => { 
        console.log("Connected Successful") 
    }) 
    .catch((err) => { 
        console.log("Error in the Connection") 
    }) 
  
// Calling Schema class 
const Schema = mongoose.Schema; 
  
// Creating Structure of the model 
const schema = new Schema({ 
    name: String, 
    address: String, 
}); 
  
// Creating the model 
schema.virtual('Introduce').get((a, b) => { 
    return this.name + ' is from ' + this.address; 
}) 
    .set((v) => { 
        let temp1 = v.split(' '); 
        this.name = temp1[0]; 
        this.address = temp1[1]; 
    }) 
  
// Compile our model 
const Person = mongoose.model('Person', schema); 
  
// Create a model 
const person = new Person({}); 
person.Introduce = 'Sam NewDelhi'; 
  
// Using the virtuals function 
console.log(person.Introduce)

Sam is from NewDelhi
Connected Successful