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Top Three Products by Region
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Top Three Products by Region

MediumSQL · PostgreSQL

Problem

Colgate-Palmolive wants a regional view of product performance for the most recently completed calendar quarter. Write a PostgreSQL query that identifies the top-selling products in each sales region.

Requirements

  1. Filter sales to the most recently completed calendar quarter relative to the fixed reporting date of August 29, 2026.
  2. Return readable region and product names.
  3. Calculate total units sold for each region and product.
  4. Rank products within each region by total units sold in descending order.
  5. Return every product whose rank is three or better, including all products tied at the third rank.

Output

  1. One row per region and product included in the top three ranks.
  2. Return region_name, product_name, total_units_sold, and product_rank.
  3. Sales with a NULL product_id are excluded because they cannot be associated with a product.
  4. Sort by region name, rank, and product name.

Schema

regions
ColumnTypeDescription
region_idPKINTUnique regional identifier
region_nameVARCHAR(100)Sales region name
products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(150)Colgate-Palmolive product name
sales
ColumnTypeDescription
sale_idPKINTUnique sales transaction identifier
region_idINTReferences regions.region_id
product_idINTReferences products.product_id
sale_dateDATEDate on which the sale occurred
units_soldINTNumber of units sold
Tablessalesregionsproducts
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