Top Campaign by Opens

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

Domain

SQL

Difficulty

medium

Seniority

mid

Problem

Our push notification system tracks opens per campaign. Find which campaign drove the most opens. An 'open' counts when the opened flag is true. If campaigns are tied at the top, show all of them.

Practice This Problem

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