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Running Totals of Daily Revenue

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

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Problem

Fashion Nova’s commerce analytics team needs a daily revenue trend for completed orders. Write a PostgreSQL query that aggregates order-item revenue by order date and calculates the cumulative revenue over time.

Requirements

  1. Include only orders with a completed status.
  2. Calculate daily revenue as quantity * unit_price, treating NULL or missing monetary values as zero.
  3. Return each revenue-producing order date, daily revenue, and running total ordered chronologically.

Schema

orders
ColumnTypeDescription
order_idPKINTEGERUnique order identifier
order_dateDATEDate the order was placed
statusVARCHAR(20)Order lifecycle status
order_items
ColumnTypeDescription
order_item_idPKINTEGERUnique order-line identifier
order_idINTEGERRelated order identifier
product_skuVARCHAR(30)Fashion Nova product SKU
quantityINTEGERUnits purchased
unit_priceNUMERIC(10,2)Price per unit
Tablesordersorder_items
Your solutionPostgreSQL
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