# Use a self join on code_reviews to find distinct pairs of authors who have reviewed the same repo

Canonical URL: <https://datadriven.io/problems/use-a-self-join-on-codereviews-to-find-distinct-pairs-of-au-d0fa5b1c>

Domain: SQL · Difficulty: medium

## Problem

Use a self join on code_reviews to find distinct pairs of authors who have reviewed the same repo. Use author_1 < author_2 to avoid duplicate pairs

## Related

- [All practice problems](https://datadriven.io/problems)
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- [SQL Interview Questions](https://datadriven.io/sql-interview-questions)
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