What happens if SQS messages partially fail in SendMessageBatch?

Question

If some messages fail and others succeed in SendMessageBatch, which of the following happens?
* No messages will be retried automatically.
* Only failed messages will be retried automatically.
* All the messages, including the succeeded ones, will be retried automatically.

Assumptions:
- All the attributes of the client API instance are set to the default.
  - e.g. `retry_limit: 3`
- No error handling on the client side except the default retry mechanics.

Answer

If some messages were sent (and in some cases, even if all messages failed), the API call will return 200. Therefor, there will not be a retry by the SDK. It is your responsibility to check the result to check which messages were sent and which failed, and act accordingly.

What happens if SQS messages partially fail in SendMessageBatch?

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