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• The crash happens between steps 1 and 3. The uncommitted data will be discarded. The input records were not committed via the EOS transaction, so the task will re-process them.
• The crash happens between 3 and 4a. The EOS transaction has been already committed, but the state store hasn't. The state store will replay the uncommitted records from the changelog topic.
• The crash happens between 4a and 4b. The state store has already committed the new records, but they are not yet reflected in the changelog topiccheckpoint file. The state store will replay the last committed records from the changelog topic. This operation is idempotent and does not violate correctness.
• The crash happens after step 4b. She The state store does nothing during recovery.

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