# For each transaction, show the username, product_name, and a safe revenue calculation (quantity time

Canonical URL: <https://datadriven.io/problems/for-each-transaction-show-the-username-productname-and-a-a9d9270a>

Domain: SQL · Difficulty: medium

## Problem

For each transaction, show the username, product_name, and a safe revenue calculation (quantity times price) that never returns NULL. Treat missing quantities as 1 and missing prices as 0.

## Related

- [All practice problems](https://datadriven.io/problems)
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