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Top-N Products With Window Functions

EasySQL · PostgreSQL00:00
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Your question is Top-N Products With Window Functions. Start with the requirements and the one table on the right.

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Problem

DICK'S Sporting Goods wants a quick view of its strongest recent product sales. Using the product_sales table, write a PostgreSQL query that finds the three products with the highest total units sold during the inclusive 30-day period from January 17, 2025 through February 15, 2025.

Requirements

  1. Exclude rows outside the 30-day period and rows with missing product, category, or unit values.
  2. Aggregate units by product and category, then return the top three products ordered by total units sold descending.

Schema

product_sales
ColumnTypeDescription
sale_idPKINTUnique sale identifier
product_nameVARCHAR(100)Product sold through DICK'S Sporting Goods
categoryVARCHAR(50)Product category
sale_dateDATEDate on which the sale occurred
units_soldINTNumber of units sold
Tablesproduct_sales
Your solutionPostgreSQL
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