{"id":"mvcc-uncommitted-data-memory-only","text":"In MVCCDatabase, uncommitted transaction writes exist only as in-memory Version objects in `_versions` and never reach a persistent data store; abort works by adding the tx_id to `_aborted` so visibility checks filter it out","truth_value":"IN","source":"entries/2026/05/29/topic-undo-logging-and-steal-policy.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"mvcc-uncommitted-data-memory-only","truth_value":"IN","reason":"premise"}]}}