Reviewed by Aditya Kumar · Last reviewed 2026-03-24
**Why techniques matter**: Combined effect = 5–50x improvement. **Partitioning**: Co-locate data; partition pruning reduces scan. Align partition key with filter. **Broadcast**: Small table to all executors; no shuffle. **Caching**: Reuse intermediates. **Scalability...
Why techniques matter: Combined effect = 5–50x improvement. Partitioning: Co-locate data; partition pruning reduces scan. Align partition key with filter. Broadcast: Small table to all executors; no shuffle. Caching: Reuse intermediates. Scalability trade-offs: Partition by high-cardinality = explosion; broadcast has size limit; cache competes with memory. Cost implications: Partition pruning = less scan; broadcast = less shuffle; cache = faster when reused. Best practice: Partition on filter columns; broadcast dimensions; cache carefully.
Red Flag: Partitioning by user_id on 1B users. Pro-Move: 'Partition by date; broadcast 5 dims; cache 1 reused DF—10x faster.'
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