# Return username and the count of transactions per user using LEFT JOIN so users with no transactions

Canonical URL: <https://datadriven.io/problems/return-username-and-the-count-of-transactions-per-user-using-144c8051>

Domain: SQL · Difficulty: medium

## Problem

Return username and the count of transactions per user using LEFT JOIN so users with no transactions appear with a 0. Use COUNT(transaction_id) AS tx_count. Order by tx_count descending, then username.

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