Database and collection creation in MongoDB - Cheat Sheet & Quick Revision

Recall & Review

beginner

How do you create a new database in MongoDB?

In MongoDB, you create a new database by switching to it using use databaseName. The database is created when you first store data in it.

beginner

What command creates a new collection explicitly in MongoDB?

Use db.createCollection('collectionName') to create a new collection explicitly.

beginner

True or False: In MongoDB, a database is created immediately when you switch to it with use.

False. The database is created only when you insert the first document into a collection within that database.

beginner

What happens if you insert a document into a collection that does not exist in MongoDB?

MongoDB automatically creates the collection and the database (if not existing) when you insert the first document.

intermediate

Explain the difference between creating a collection explicitly and implicitly in MongoDB.

Explicit creation uses db.createCollection(). Implicit creation happens automatically when you insert a document into a non-existing collection.

Which command switches to a database named 'shop' in MongoDB?

A use shop

B db.shop()

C create database shop

D switch shop

The use shop command switches to the 'shop' database.

How do you explicitly create a collection named 'products'?

A db.products.insert()

B use products

C create collection products

D db.createCollection('products')

Use db.createCollection('products') to explicitly create a collection.

When is a MongoDB database actually created?

A When you run <code>use</code> command

B When you create a collection explicitly

C When you insert the first document

D When you start the MongoDB server

The database is created when the first document is inserted into a collection.

What happens if you insert a document into a non-existing collection?

A Collection and database are created automatically

B Error is thrown

C Nothing happens

D You must create collection first

MongoDB creates the collection and database automatically on first insert.

Which of these is NOT a way to create a collection in MongoDB?

A Using db.createCollection()

B Using SQL CREATE TABLE command

C Inserting a document into a new collection

D Switching to a new database with use command

SQL commands like CREATE TABLE do not work in MongoDB.

Describe the process of creating a new database and collection in MongoDB.

Think about what happens when you insert data.

Explain the difference between implicit and explicit collection creation in MongoDB.

One is manual, the other automatic.