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Top Categories in 30 Days
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Top Categories in 30 Days

MediumSQL · PostgreSQL

Problem

Write a query to identify top-selling categories over a rolling 30-day window at Etsy.

Use February 28, 2025 as the reporting date. Consider completed sales from February 1 through February 28, inclusive, and return the top three categories by units sold.

Output

  1. One row per top-three category with category_name, total_units_sold, total_revenue, and sales_rank.
  2. Rank ties equally and order by sales_rank ascending, then category_name ascending.

Schema

categories
ColumnTypeDescription
category_idPKINTUnique Etsy listing category identifier
category_nameVARCHAR(100)Display name of the category
category_descriptionTEXTOptional category description
sales
ColumnTypeDescription
sale_idPKINTUnique sale identifier
category_idINTCategory associated with the sold listing
order_dateDATEDate of the sale
quantityINTNumber of units in the sale
gross_amountNUMERIC(12,2)Gross sale revenue before adjustments
statusVARCHAR(20)Sale processing status
Tablessalescategories
Interviewer

Your question is Top Categories in 30 Days. Start with the requirements and the two tables in the Question tab.

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