MongoDB CRUD Operations Examples

Insert and Query Users

Insert three user documents with different ages, then query all users older than 20.

Expected output: A list of user documents with age greater than 20.

Hint: Use insertMany() for insertion and find() with a filter for querying.

Update User Email

Update the email address of a user named 'Bob' to a new email.

Expected output: The user document for Bob has the updated email.

Hint: Use updateOne() with a filter on the name and $set operator for the email.

Delete Users by Age

Delete all users younger than 18 from the collection.

Expected output: All user documents with age less than 18 are removed.

Hint: Use deleteMany() with a filter on the age field.

The main CRUD operations are Create (insertOne, insertMany), Read (find, findOne), Update (updateOne, updateMany), and Delete (deleteOne, deleteMany).

Use updateOne() with the $set operator to update a specific field in a document.

Calling deleteMany() without a filter deletes all documents in the collection, which can cause data loss.