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Write a query to retain only the latest record and delete others in case of duplicates.

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
Fossil Group
Key Concepts Tested
partition
Expert AnswerPremium
67 wordsInterview-ready
WITH ranked AS (SELECT *, ROW_NUMBER() OVER (PARTITION BY business_key ORDER BY updated_at DESC) AS rn FROM my_table) DELETE FROM my_table t WHERE EXISTS (SELECT 1 FROM ranked r WHERE r.business_key = t.business_key AND r.updated_at = t.updated_at AND r.rn > 1). **Why**: ORDER BY updated_at DESC keeps latest. Alternative: create new table with latest, swap....
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