Top 10 Data Engineering Interview Prep Tools (2026 Guide for SQL, ETL & System Design)

A curated comparison of 10 interview prep platforms for data engineering roles in 2026, covering SQL, Python, ETL, data modeling, and system design. Tools are rated and reviewed with pros/cons, ranging from DataDriven and StrataScratch for realistic interview practice, to Coursera for structured learning, LeetCode for DSA fundamentals, and interviewing.io for live mock interviews. The guide advises combining tools strategically rather than relying on any single platform.