Reviewed by Aditya Kumar · Last reviewed 2026-03-24
Cassandra: distributed NoSQL, wide-column store. Ring topology, partition key determines node; clustering columns for sort order. Tunable consistency (ONE, QUORUM, ALL). CQL for queries. Good for: high write throughput, geo-distribution, no single point of failure. Model by...
Cassandra: distributed NoSQL, wide-column store. Ring topology, partition key determines node; clustering columns for sort order. Tunable consistency (ONE, QUORUM, ALL). CQL for queries. Good for: high write throughput, geo-distribution, no single point of failure. Model by query pattern; denormalize. Unlike SQL: no joins, limited aggregations, eventual consistency options. Why it matters: Design choices compound at scale—wrong approach can cause 100× overhead. Scalability trade-offs: Profile before optimizing; validate on sample then full. Cost implications: Suboptimal choices multiply at billion-row scale.
Red Flag: Generic textbook answers. Pro-Move: 'At scale we measured X, implemented Y, achieved Z%—validated and iterated.'
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