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SQL Data Cleaning & Transformation Practice

Master SQL data cleaning techniques including COALESCE, NULLIF, CASE WHEN, string manipulation, type casting, deduplication with ROW_NUMBER, and handling NULL values. These are the skills you use daily in real-world analytics and data engineering.

SQL Problems

Practice SQL Problems

Difficulty Breakdown

57 problems

20 Easy(35%)

24 Medium(42%)

13 Hard(23%)

0 Expert(0%)

Skills You'll Practice

62 skills

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