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Pivoting Data for Reporting
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Pivoting Data for Reporting

MediumSQL · PostgreSQL

Problem

How would you use pivoting to reshape data for reporting?

Use the provided product and sales tables to produce a reporting-ready result for the first quarter of 2025.

Output

  1. One row per product, including products with no qualifying sales.
  2. Columns: category, product_name, january_sales, february_sales, march_sales, and q1_sales.
  3. Include only sales dated from January 1 through March 31, 2025. Treat missing monthly sales as zero.
  4. Sort by category, then product_name ascending.

Schema

products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(100)Product name
categoryVARCHAR(60)Product category
sales
ColumnTypeDescription
sale_idPKINTUnique sale identifier
product_idINTProduct associated with the sale
sale_dateDATEDate of the sale
net_salesNUMERIC(12,2)Net sales amount, which may be null when not recorded
Tablesproductssales
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