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SQL Sales by Category
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SQL Sales by Category

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the total sales for each product category in the last quarter.

Use the calendar quarter immediately preceding CURRENT_DATE. Include categories with no qualifying sales and report their total as zero.

Output

  1. One row per product category, with category_name and total_sales.
  2. Include only sales dated within the preceding calendar quarter.
  3. Order by total_sales descending, then category_name ascending to break ties.

Schema

categories
ColumnTypeDescription
category_idPKINTUnique product category identifier
category_nameVARCHAR(100)Product category name
products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(150)Product name
category_idINTCategory assigned to the product
sales
ColumnTypeDescription
sale_idPKINTUnique sale identifier
product_idINTProduct sold
sale_dateDATEDate of the sale
quantityINTNumber of units sold
unit_priceNUMERIC(10,2)Price per unit
Tablescategoriesproductssales
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