# For each API call, show the endpoint, username (NULL when no user matches), and classify the status:

Canonical URL: <https://datadriven.io/problems/for-each-api-call-show-the-endpoint-username-null-when-no-ea815b80>

Domain: SQL · Difficulty: medium

## Problem

For each API call, show the endpoint, username (NULL when no user matches), and classify the status: 'success' for 200, 'error' for other non-NULL values, 'unknown' when NULL.

## Related

- [All practice problems](https://datadriven.io/problems)
- [Mock interview mode](https://datadriven.io/interview/for-each-api-call-show-the-endpoint-username-null-when-no-ea815b80)
- [SQL Interview Questions](https://datadriven.io/sql-interview-questions)
- [Data Engineering Interview Prep Guide](https://datadriven.io/data-engineer-interview-prep)
- [Daily Challenge](https://datadriven.io/daily)

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