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SQL

SQL “TOP 1 WITH ORDER BY” Without Index = Full Scan

- 15.12.25 - ErcanOPAK

This query is slow without the right index:

SELECT TOP 1 * 
FROM Orders 
ORDER BY CreatedAt DESC;

✅ Correct Index

CREATE INDEX IX_Orders_CreatedAt 
ON Orders (CreatedAt DESC);

Result

  • Instant response

  • No table scan

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Post Views: 6

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