MongoDB CRUD Operations

General Constraints

CRUD operations share these constraints:

• Target scope: Operations target a single collection.

• Atomicity: All write operations are atomic on the level of a single document.

• Filter syntax: Update and delete operations use the same filter syntax as read operations.

Create Operations

Create or insert operations add new documents to a collection. MongoDB creates the collection if it doesn't exist.

Methods

MongoDB provides the following methods to insert documents into a collection:

• db.collection.insertOne()

• db.collection.insertMany()

For examples, see Create Documents.

Read Operations

Read operations retrieve documents from a collection.

Methods

MongoDB provides the following methods to read documents from a collection:

• db.collection.find()

Use query filters to specify which documents to return.

For examples, see:

• Read Documents

• Query on Embedded/Nested Documents

• Query an Array

• Query an Array of Embedded Documents

Update Operations

Update operations modify existing documents in a collection.

Methods

MongoDB provides the following methods to update documents of a collection:

• db.collection.updateOne()

• db.collection.updateMany()

• db.collection.replaceOne()

Use filters to specify which documents to update.

For examples, see Update Documents.

Delete Operations

Delete operations remove documents from a collection.

Methods

MongoDB provides the following methods to delete documents of a collection:

• db.collection.deleteOne()

• db.collection.deleteMany()

Use filters to specify which documents to remove.

For examples, see Delete Documents.

Bulk Write

MongoDB provides the ability to perform multiple write operations in bulk. See Bulk Write Operations.