# For each ad campaign, count the total number of impressions and the number of distinct users who saw

Canonical URL: <https://datadriven.io/problems/for-each-ad-campaign-count-the-total-number-of-impressions-f39f2c09>

Domain: SQL · Difficulty: medium

## Problem

For each ad campaign, count the total number of impressions and the number of distinct users who saw the ad.

## Related

- [All practice problems](https://datadriven.io/problems)
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- [Data Engineering Interview Prep Guide](https://datadriven.io/data-engineer-interview-prep)
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