Batch delete patterns in Rest API - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Batch delete using query parameters

Consider a REST API endpoint that deletes multiple users by IDs passed as query parameters.

What is the expected HTTP response status code when the following DELETE request is successful?

DELETE /users?ids=1,2,3

A 500 Internal Server Error if any user ID is invalid

B 200 OK with a JSON body listing deleted user IDs

C 404 Not Found if any user ID does not exist

D 204 No Content with an empty response body

💡 Hint

Think about the standard REST practice for successful DELETE requests with no content returned.

204 No Content is the standard response for successful DELETE requests when no response body is returned. Returning 200 OK with a body is possible but less common. 404 or 500 indicate errors.

❓ Predict Output

intermediate

Batch delete with JSON body payload

A REST API supports batch deletion by sending a JSON array of IDs in the request body.

Given this request:

DELETE /items
Content-Type: application/json

[10, 20, 30]

What is the expected output if items 10 and 20 exist but 30 does not?

A {"deleted": [10, 20], "not_found": [30]}

B 204 No Content with empty body

C 404 Not Found with error message for ID 30

D 400 Bad Request due to invalid ID 30

💡 Hint

Consider how partial success is usually reported in batch operations.

When some items are deleted and some are missing, the API commonly returns a JSON object listing which were deleted and which were not found. 204 No Content would not convey partial success. 404 or 400 would reject the entire request.

🧠 Conceptual

advanced

Idempotency in batch delete operations

Why is idempotency important in batch delete REST API endpoints?

A To ensure repeated requests do not cause errors or duplicate deletions

B To allow the server to reject duplicate requests automatically

C To guarantee the server deletes all items regardless of request content

D To require clients to send unique tokens with each request

💡 Hint

Think about what happens if a client sends the same delete request multiple times.

Idempotency means that making the same request multiple times has the same effect as making it once. This prevents errors or unintended side effects from repeated requests.

🔧 Debug

advanced

Debugging batch delete with partial failure

A batch delete API returns this JSON response:

{"deleted": [1, 2], "errors": [{"id": 3, "message": "Permission denied"}]}

What is the most likely cause of this partial failure?

A The request body format is invalid for ID 3

B Item with ID 3 does not exist in the database

C User lacks permission to delete item with ID 3

D The server crashed while deleting item 3

💡 Hint

Look at the error message associated with ID 3.

The error message "Permission denied" indicates the user is not authorized to delete item 3, causing partial failure while other items were deleted successfully.

📝 Syntax

expert

Correct batch delete request format

Which of the following HTTP DELETE requests correctly uses a JSON body to batch delete resources?

A

DELETE /resources
Content-Type: text/plain

ids=5,6,7

B

DELETE /resources
Content-Type: application/json

{"ids": [5, 6, 7]}

C

DELETE /resources
Content-Type: application/json

[5, 6, 7]

D

DELETE /resources/5,6,7
Content-Type: application/json

{}

💡 Hint

Consider the correct use of HTTP method, URL, headers, and body format for batch delete.

Option B correctly sends a DELETE request to the resource endpoint with a JSON body containing an object with an "ids" array. Option B sends a JSON array directly which some APIs may not accept. Option B uses an invalid URL format. Option B uses wrong content type and body format.