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Top Product Lines SQL
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Top Product Lines SQL

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the top three highest-grossing product lines in the last quarter, partitioning by region.

Assume the last quarter is Q2 2025, from April 1 through June 30. Include completed sales only. Ties at the third position should be included.

Output

  1. One row per qualifying region and product line.
  2. Columns: region_name, product_line_name, total_revenue, and revenue_rank.
  3. Sort by region_name, revenue_rank, then product_line_name.

Schema

regions
ColumnTypeDescription
region_idPKINTUnique region identifier
region_nameVARCHAR(100)Business region name
product_lines
ColumnTypeDescription
product_line_idPKINTUnique product-line identifier
product_line_nameVARCHAR(150)Product-line name
sales_transactions
ColumnTypeDescription
sale_idPKINTUnique sales transaction identifier
region_idINTRegion associated with the sale
product_line_idINTProduct line associated with the sale
sale_dateDATEDate of the sale
quantityINTUnits sold
unit_priceNUMERIC(12,2)Price per unit
statusVARCHAR(30)Transaction status
Tablesregionsproduct_linessales_transactions
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