Which API operations are idempotent and why are they important for address management?

Which API operations are idempotent and why are they important for address management?

• A. GET and POST
• B. PUT and DELETE
• C. POST and PATCH
• D. GET and PATCH

Answer: (B)

Idempotence in API operations means repeating the same request yields the same final state as doing it once. This is crucial for address management because network retries or repeated requests should not create duplicates or cause inconsistent states.

A PUT request to a specific address resource replaces that address with the provided data. If you send the same PUT again, the result is the same address data at that resource—no extra addresses are created and no additional changes occur. This makes PUT reliable to retry without side effects.

A DELETE request removes the address resource. If the same DELETE is issued again, the final state remains the same—the address is gone. Retries won’t accumulate more deletions or alter other data, which is exactly what you want for predictable cleanup.

While GET is also idempotent, it only reads data and does not modify state, so it’s not the focus when discussing operations that change address records. POST, on the other hand, typically creates new resources and can produce duplicates if retried, so it isn’t idempotent in this context. PATCH can be idempotent in some designs, but it often applies incremental changes that might stack on repeated calls unless carefully implemented.