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How do you pivot rows into columns in SQL (conditional aggregation)?

Pivoting (rows to columns) is constant in analytics and reporting, and the portable trick is conditional aggregation, not a vendor PIVOT clause. The signal is the CASE-inside-aggregate pattern and knowing its one real limit.

Updated Aug 2026 · Grounded in real Applied AI Engineer interview loops and written to a senior-engineer editorial bar.

Pivoting (rows to columns) is constant in analytics and reporting, and the portable trick is conditional aggregation, not a vendor PIVOT clause. The signal is the CASE-inside-aggregate pattern and knowing its one real limit.

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