Data Quality

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

Domain

SQL

Difficulty

hard

Problem

The data engineering team wants to identify databases with a clean migration record. For each database, compute the total number of migrations and total rollbacks. Only return databases that have never had a rollback.

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.