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

Domain

SQL

Difficulty

easy

Seniority

L3

Problem

The growth team is tracking daily cross-platform engagement for mobile and web users. For each date, count the unique users who had at least one session on a 'mobile' or 'web' device. Show the date and the user count, chronologically.

Summary

Mobile and web. Same day, same users?

Practice This Problem

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