# The users table has user_id, username, and email

Canonical URL: <https://datadriven.io/problems/the-users-table-has-userid-username-and-email-some-users-c9ad8872>

Domain: SQL · Difficulty: medium

## Problem

The users table has user_id, username, and email. Some users did not provide their email, so it is stored as NULL. Write a query to show the username of every user whose email is unknown.

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