# For each user, show their username and the total number of distinct product categories they have pur

Canonical URL: <https://datadriven.io/problems/for-each-user-show-their-username-and-the-total-number-of-d-61e0b9d0>

Domain: SQL · Difficulty: medium

## Problem

For each user, show their username and the total number of distinct product categories they have purchased, counting NULL as a separate category if present. Name it category_count.

## Related

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