# For each user, show their username and a list of distinct product categories they have purchased as

Canonical URL: <https://datadriven.io/problems/for-each-user-show-their-username-and-a-list-of-distinct-pr-81c24fd3>

Domain: SQL · Difficulty: medium

## Problem

For each user, show their username and a list of distinct product categories they have purchased as unique_categories.

## Related

- [All practice problems](https://datadriven.io/problems)
- [Mock interview mode](https://datadriven.io/interview/for-each-user-show-their-username-and-a-list-of-distinct-pr-81c24fd3)
- [SQL Interview Questions](https://datadriven.io/sql-interview-questions)
- [Data Engineering Interview Prep Guide](https://datadriven.io/data-engineer-interview-prep)
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