DeleteItem in DynamoDB - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the DeleteItem operation do in DynamoDB?

It removes a single item from a DynamoDB table based on its primary key.

beginner

Which key attribute(s) must you provide to delete an item using DeleteItem?

You must provide the full primary key of the item, which can be a partition key alone or a partition key and sort key if the table uses both.

beginner

What happens if you try to delete an item that does not exist in the table?

The operation succeeds but no item is deleted because the item was not found.

intermediate

How can you conditionally delete an item only if a certain attribute has a specific value?

Use a ConditionExpression in the DeleteItem request to specify the attribute condition that must be true for the deletion to proceed.

intermediate

What is returned by the DeleteItem operation if you request to return the deleted item's attributes?

You can request ReturnValues set to ALL_OLD to get the attributes of the deleted item before it was removed.

What is the minimum information needed to delete an item in DynamoDB using DeleteItem?

A Primary key of the item

B All attributes of the item

C Table name only

D Partition key and a filter expression

You only need to provide the primary key (partition key, and sort key if applicable) to delete an item.

If you want to delete an item only when an attribute "status" equals "active", what should you use?

A ProjectionExpression

B FilterExpression

C ConditionExpression

D ReturnValues

ConditionExpression lets you specify conditions that must be true for the delete to happen.

What does ReturnValues: ALL_OLD do in a DeleteItem request?

A Returns nothing

B Returns all items in the table

C Returns only the primary key of the deleted item

D Returns the deleted item's attributes before deletion

ALL_OLD returns the full item attributes as they were before deletion.

What happens if you delete an item that does not exist?

A Operation succeeds but no item is deleted

B Operation fails with an error

C Table is deleted

D A new item is created

Deleting a non-existent item does not cause an error; it just does nothing.

Which of these is NOT a valid part of a DeleteItem request?

A Key

B UpdateExpression

C ReturnValues

D ConditionExpression

UpdateExpression is used in update operations, not delete.

Explain how you would delete an item from a DynamoDB table using the DeleteItem operation.

Think about what uniquely identifies the item and how to ensure safe deletion.

Describe what happens behind the scenes when you call DeleteItem on an item that does not exist.

Consider how DynamoDB treats missing items on delete.