# Successful Call Volume per Endpoint

> Not every ping is honest.

Canonical URL: <https://datadriven.io/problems/successful_call_volume_per_endpoint>

Domain: SQL · Difficulty: medium · Seniority: L5

## Problem

The API gateway logs duplicate events from retry middleware. In the api_calls table, duplicate rows share the same user_id, endpoint, and call_time. Keep only the row with the lowest call_id from each duplicate group. After deduplication, find the total number of successful calls per endpoint. A successful call has status equal to 200. Return each endpoint and its successful call count, ordered from most to fewest.

## Related

- [All practice problems](https://datadriven.io/problems)
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