What is an operation's idempotency property?

Idempotency of an operation means that performing the same operation multiple times with the same input data will not change the state of the system after the first call — the result will be the same as if the operation was performed once.

In the context of web services and APIs, idempotency is important for ensuring reliability: if a request is repeated due to network failures or errors, it will not lead to unwanted side effects.

Example: The HTTP method PUT is usually idempotent — if you send a request to update a resource multiple times with the same data, the state of the resource will remain unchanged after the first update.

In Go, idempotency is often considered when designing APIs and database operations to avoid duplication or data inconsistency.