# Self-join user_sessions to find distinct pairs of devices used by the same user

Canonical URL: <https://datadriven.io/problems/self-join-usersessions-to-find-distinct-pairs-of-devices-us-99de05f8>

Domain: SQL · Difficulty: medium

## Problem

Self-join user_sessions to find distinct pairs of devices used by the same user. Return user_id and both device values, keeping the lower device first.

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