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

Domain

SQL

Difficulty

medium

Seniority

L5

Problem

Calculate the conversion rate from free signup to paid subscription, broken down by referral source. The growth team wants to decide where to increase ad spend next quarter. Round to 4 decimal places.

Summary

Signups are one thing. Paid subscriptions are another. Find the gap.

Practice This Problem

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