# Use a FULL OUTER JOIN between users and content_items, matching user_id to creator_id

Canonical URL: <https://datadriven.io/problems/use-a-full-outer-join-between-users-and-contentitems-match-bbeb5f8b>

Domain: SQL · Difficulty: medium

## Problem

Use a FULL OUTER JOIN between users and content_items, matching user_id to creator_id. Return username and title so you can see users who created no content and content with no matching user.

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