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Running Total of Daily Revenue

MediumSQL · PostgreSQL00:00
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Your question is Running Total of Daily Revenue. Start with the requirements and the two tables on the right.

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Problem

Business context

MORSE needs a product-level revenue view for monitoring performance across its analytics surfaces. Revenue should include completed sales only, while products without completed sales should not appear in the result.

Task

Write a PostgreSQL query that calculates daily revenue and a chronological running total for each product from January 1 through January 5, 2024.

Requirements

  1. Join products to sales using product_id.
  2. Include only rows whose status is completed and whose sale_date is within the requested date range.
  3. Aggregate multiple sales for the same product and day into daily_revenue, treating NULL revenue as zero.
  4. Use a window function to calculate running_total independently for each product, ordered by sale date. Return products by name and date.

Schema

products
ColumnTypeDescription
product_idPKINTEGERUnique product identifier
product_nameVARCHAR(100)Name displayed for the product
sales
ColumnTypeDescription
sale_idPKINTEGERUnique sale identifier
product_idINTEGERProduct associated with the sale
sale_dateDATECalendar date on which the sale occurred
revenueNUMERIC(12,2)Revenue credited to the sale
statusVARCHAR(20)Lifecycle status of the sale
Tablesproductssales
Your solutionPostgreSQL
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