Most Efficient High-Volume Campaign

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

Domain

SQL

Difficulty

hard

Seniority

mid, senior

Problem

We want the campaign with the lowest peak monthly spend that still delivers at least 1 click every month it runs. Monthly clicks are the sum of clicked impressions, and monthly spend is the sum of revenue. Return just the campaign name.

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.