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Explain indexing and its impact on database performance.

SQLmedium0.3 min readPremium
Frequency
Low
Asked at 1 company
Category
487
questions in SQL
Difficulty Split
130E|271M|86H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Goldman Sachs
Key Concepts Tested
bigqueryjoinpartitionsnowflake
Expert AnswerPremium
59 wordsInterview-ready
**Architectural Logic**: Indexes speed reads; cost writes—balance by workload. **Mechanism**: B-tree (range), hash (equality), bitmap (low cardinality). Speeds WHERE, JOIN, ORDER BY. **Impact**: Read faster; INSERT/UPDATE slower (maintenance). **Scalability**: Strategic indexing; avoid over-indexing. **Warehouses**: BigQuery, Snowflake use partitioning + clustering instead of B-tree. **OLTP**: Indexes critical....
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