# Find usernames that have NO transactions

Canonical URL: <https://datadriven.io/problems/find-usernames-that-have-no-transactions-use-left-join-and-77b1ccb4>

Domain: SQL · Difficulty: medium

## Problem

Find usernames that have NO transactions. Use LEFT JOIN and WHERE t.transaction_id IS NULL. Return just the username ordered ascending.

## Related

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