# Use APPROX_DISTINCT to estimate the number of unique users who have made transactions

Canonical URL: <https://datadriven.io/problems/use-approxdistinct-to-estimate-the-number-of-unique-users-w-eaff1c4c>

Domain: SQL · Difficulty: medium

## Problem

Use APPROX_DISTINCT to estimate the number of unique users who have made transactions. Label the result estimated_unique_users.

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