Reviewed by Aditya Kumar · Last reviewed 2026-03-24
Performance: indexing, partitioning, query rewrite, statistics. Temporal tables: system-versioned tables for point-in-time queries. Use for auditing, history. Example: SELECT * FROM employee FOR SYSTEM_TIME AS OF '2024-01-01'. Combines current and historical in one query. **Why...
Performance: indexing, partitioning, query rewrite, statistics. Temporal tables: system-versioned tables for point-in-time queries. Use for auditing, history. Example: SELECT * FROM employee FOR SYSTEM_TIME AS OF '2024-01-01'. Combines current and historical in one query. 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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