# From users, return COUNT(*) AS total_users and COUNT(age_bucket) AS with_age on one row; then subtra

Canonical URL: <https://datadriven.io/problems/from-users-return-count-as-totalusers-and-countagebuc-1be18036>

Domain: SQL · Difficulty: medium

## Problem

From users, return COUNT(*) AS total_users and COUNT(age_bucket) AS with_age on one row; then subtract to derive missing_age as total_users - with_age, also on the row.

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