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SQL for Top Categories
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SQL for Top Categories

MediumSQL · PostgreSQL

Problem

Write a query to find the top three performing categories in a sales dataset.

Use the provided categories and sales tables. Performance is measured by total sale amount. Include categories with no matching sales as zero, and exclude sales that cannot be associated with a category.

Output

  1. Return one row per category with category_name and total_sales.
  2. Return only the three highest totals.
  3. Order by total_sales descending, then category_name ascending to break ties.

Schema

categories
ColumnTypeDescription
category_idPKINTUnique category identifier
category_nameVARCHAR(100)Category name
sales
ColumnTypeDescription
sale_idPKINTUnique sale identifier
category_idINTCategory associated with the sale
sale_amountNUMERIC(12,2)Amount recorded for the sale
Tablescategoriessales
Interviewer

Your question is SQL for Top Categories. Start with the requirements and the two tables in the Question tab.

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