hardDSA

How do you pivot rows into columns?

Q: How do you pivot rows into columns?

Use conditional aggregation: `SELECT year, SUM(CASE WHEN q='Q1' THEN amt END) AS q1, ... GROUP BY year`. Some databases offer a `PIVOT` operator. It transforms row values into columns for cross-tab reports.

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Use conditional aggregation: SELECT year, SUM(CASE WHEN q='Q1' THEN amt END) AS q1, ... GROUP BY year. Some databases offer a PIVOT operator. It transforms row values into columns for cross-tab reports.

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