Mutual Channel Connections

A medium SQL interview practice problem on DataDriven. Write and execute real sql code with instant grading.

Domain

SQL

Difficulty

medium

Seniority

L4

Problem

Our messaging platform tracks which senders post in which channels. Find all sender IDs that appear in at least one channel where user 197 posted and also in at least one channel where user 585 posted, excluding those two users themselves.

Summary

Two users. What channels do they share?

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