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JavaScript Object-Oriented JavaScript Object Basics Changing and Adding Properties

Posted by Murilo de Melo
Murilo de Melo
14,456 Points

Do properties created on the fly to objects become persistent in the DB or just accessible while the program is running?

I've seen many examples of properties created after the object has been created, dynamically. But It's not clear to me whether this can be made persistent for later access or can only be used while the program is running.

Tnx

1 Answer

Byron Injeeli
.a{fill-rule:evenodd;}techdegree seal-36
Byron Injeeli
Full Stack JavaScript Techdegree Graduate 25,639 Points

Hi Murilo. Let's say that you create a new user like this:

db.create({
    email: req.body.email,
    username: req.body.name
}, (err, user) => {
    console.log(user);
});

Maybe you add a new property on this user object like this:

user.age = 31;

The user object will not be saved until you update the object with another method like this:

db.updateUser(user, (err, updatedUser) => {
    console.log('User updated.');
});

You can create your own custom methods (functions) to update/delete/create users using MongoDB.