⚡ SQL Visual Debugger & Interactive Studio

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Easy Self Joins & NULL Handling

1. Scott/Tiger: Employees & Their Direct Managers

Medium Multi-Table Joins & Non-Equi Joins

2. Scott/Tiger: Department Salary Grades Breakdown

Easy Window Functions & Aggregation

3. Second Highest Salary (LeetCode #176)

Hard DENSE_RANK & Partitioning

4. Department Top 3 Salaries (LeetCode #185)

Medium OTT Media Analytics & Partitioning

5. Netflix OTT: Top 3 Most Streamed Titles per Genre

Easy GPU Infrastructure & Cost Analysis

6. AI Compute: Expensive Training Runs Exceeding $500k

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                ROW_NUMBER() OVER (PARTITION BY d ORDER BY sal DESC)

                DENSE_RANK() OVER (PARTITION BY d ORDER BY sal DESC)


                LAG(val, 1) OVER (ORDER BY date_col)

                LEAD(val, 1) OVER (ORDER BY date_col)


                COALESCE(comm, 0)

                NULLIF(a, b)

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