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SQL Sales by Category
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SQL Sales by Category

MediumSQL · PostgreSQL

Problem

Can you write a SQL query to find the total sales for each product category at Lloyd’s Market?

Use the provided category, product, and sales tables. Include categories with no matching sales and treat missing sale amounts as contributing zero.

Output

  1. One row per product category, with category_name and total_sales.
  2. Include all categories, including those with no sales.
  3. Sort by total_sales descending, then category_name ascending for ties.

Schema

product_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_idINTProduct category identifier
sales
ColumnTypeDescription
sale_idPKINTUnique sale identifier
product_idINTSold product identifier
sale_amountNUMERIC(12,2)Recorded sale amount
Tablesproduct_categoriesproductssales
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Your question is SQL Sales by Category. Start with the requirements and the three tables in the Question tab.

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CodePostgreSQL
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