{"id":"hash-mod-destroys-key-order","text":"Hash-mod partitioning (`hash(k) % num_reducers`) scatters lexicographically adjacent keys across different partitions, making range queries require a full scatter-gather across all reducers; MapReduce `run()` re-sorts the final results to compensate","truth_value":"IN","source":"entries/2026/05/29/topic-hash-partitioning-skew.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"hash-mod-destroys-key-order","truth_value":"IN","reason":"premise"}]}}