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

Domain

SQL

Difficulty

medium

Seniority

L4

Problem

For each device type, count users who have only ever used that single device type across all their sessions. Return the device type and exclusive user count.

Summary

Loyal to one platform only.

Practice This Problem

Solve this SQL problem with real code execution. DataDriven runs your SQL queries against a real database and grades it automatically.