MongoDB CRUD operations

Create, read, update, and delete (CRUD) operations, are the basic interactions you perform with a database. To execute CRUD operations over your database entities, MongoDB provides various collection methods.

Creating a new document

You're already familiar with the basic method of creating a new document using the insert() method, as you previously did in earlier examples. Besides the insert() method, there are two more methods called update() and save() to create new objects.

Creating a document using insert()

The most common way to create a new document is to use the insert() method. The insert method takes a single argument that represents the new document. To insert a new post, just issue the following command in the MongoDB shell:

> db.posts.insert({"title":"Second Post", "user": "alice"})

Creating a document using update()

The update() method is usually used to update an existing document. You can also use it to create a new document, if no document matches the...