Technical interview practice
SQL indexes
What are database indexes and when should you use them?
Try answering aloud before opening the example. Explain the distinction, give a practical use case, and name a trade-off or exception. The aim is a clear explanation in your own words.
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Illustrative example
An index can provide faster lookups without a full table scan. It introduces write overhead and uses extra storage.
2 of 4 concepts covered
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