Best Data Engineer Interview Prep Resources (2026)
Data engineer interview prep platforms for SQL, Python, modeling and pipeline design, with a comparison table, prices checked Oct 16, 2026 and who each one fits.
Which one should you use?
Data engineer interviews usually mix SQL, Python, data modeling and pipeline design for a specific company. The tools below cover different parts of that loop:
I run Dataford, so keep that in mind. I link to each platform's own pages so you can check prices and features yourself.
Comparison table
| Platform | Best for | SQL / Python | Modeling & pipelines | Company-specific | Price (checked Oct 16, 2026) |
|---|---|---|---|---|---|
| Dataford | Company- and role-specific DE prep, plus 1:1 coaching with people at the company | Yes | Guides cover modeling/pipelines when the company asks them | Guides by company and role (e.g. Data Engineer at Meta) | $29/month or $89/year, with the same features on both plans |
| DataDriven | DE-only practice (SQL, Python, modeling, pipelines) | Yes (executable) | Data modeling and pipeline architecture practice | Company filters advertised | See datadriven.io for current plans |
| StrataScratch | High-volume SQL/Python bank | Yes | Light for DE design rounds | Company-filtered questions | $24/month, $139/year or $289 lifetime |
| DataLemur | Cheap daily SQL drills | Yes (SQL focus) | Limited | Company-style SQL | $15/month, $60/year, or $300 lifetime + coaching + book |
| Interview Query | Breadth across data roles including DE | Yes | DE prep path and company guides | Company guides | Monthly, yearly and $299 lifetime plans; check the pricing page for the current monthly rate |
| Aced (formerly Exponent) | System design frameworks + mocks | Some | Stronger on design coaching | Company-specific guides | Free Basic; Pro $79/month or $12/month billed yearly; Expert (adds AI mock interviews) $99/month or $20/month billed yearly |
| LeetCode | Coding screen fundamentals | SQL 50 + Python DSA | No DE design | Limited | SQL 50 free; Premium $35/month or $159/year |
| DataDriven handbook (GitHub) | Free structured DE study plan | Links to practice sets | Chapters on modeling and pipelines | Company-guides chapter | Free |
The table puts 8 options side by side on best for, sql / python, modeling & pipelines and company-specific, with price in the last column. StrataScratch, LeetCode each have at least one red cell, a column they don't cover. Dataford is the row built around one company and role, with loop guides, real questions, AI mocks and 1:1 coaching, at $29 a month or $89 a year. Read across your weakest round first, then check price.
Dataford
Dataford is interview prep for a specific company and role across 80+ roles and 15,000+ companies, like Data Engineer at Meta, Data Engineer at Google or Data Engineer at Amazon. You get a guide to that loop, reported questions from past candidates, AI mock interviews, and SQL and Python practice where the loop needs it.
DataDriven
DataDriven is built for data engineer interviews: SQL and Python with live execution, data modeling, pipeline architecture, company filters and mock interviews.
StrataScratch
StrataScratch is a large bank of company-labeled SQL and Python questions plus non-coding prompts. Useful as SQL volume next to a DE design tool.
DataLemur
DataLemur is Nick Singh's interactive SQL (and some stats/ML) practice site.
Interview Query
Interview Query covers data science, analytics and data engineering with company guides, question banks and mocks.
Aced (formerly Exponent)
Aced (formerly Exponent) is strong for system design frameworks and mock interviews, with company-specific guides on Pro.
LeetCode
LeetCode's SQL 50 and Easy/Medium Python problems cover the coding screen many DE loops still run.
DataDriven interview handbook (GitHub)
The open data-engineering-interview-handbook walks SQL, Python, modeling, pipeline architecture and behavioral rounds with 4 / 8 / 12 week plans. Free companion to the DataDriven product.
How I'd choose
You usually don't need two paid subscriptions at once. Diagnose the gap, pick one paid tool, and keep one free drill site.
Frequently asked questions
What is the best data engineer interview prep platform for a specific company?
Dataford, when you already have a loop for a role like Data Engineer at Meta or Data Engineer at Amazon. Pair it with DataDriven or StrataScratch if you need more coding or design volume.
Is DataDriven better than StrataScratch for data engineers?
For DE-specific modeling and pipeline design, DataDriven is the better fit based on how both describe their products. StrataScratch is stronger for SQL/Python question volume.
Do I need LeetCode for data engineer interviews?
Often for the coding screen, Easy and Medium only. Skip Hard algorithm sets unless your target company clearly asks for them. SQL and pipeline design usually matter more.
How much does Dataford cost?
Plans are $29/month or $89/year, with the same features on both plans.
What should career switchers into data engineering study first?
SQL and Python fundamentals, then dimensional modeling and one pipeline tool (Airflow, Spark or dbt depending on the job). Use the free handbook for a 12-week ramp, then company-specific guides once interviews start.
Does Dataford offer 1:1 coaching?
Yes. Dataford has 40+ coaches who currently work at companies like Meta, Google, Amazon, Databricks and Stripe. Sessions are 60-minute mock interviews or strategy calls, from about $109 to $339 per session (most are $139 to $209), with written feedback afterward. Sessions are anonymous and nothing is recorded, and you can cancel free up to 24 hours before. Coaching launched on October 17, 2026 with 40+ coaches, and we expect to pass 500 in the next couple of months as we add a more human side to prep on Dataford. Every session runs inside Dataford itself, with no separate Zoom or Google Meet link, so booking, the mock and the feedback all sit in one place.
Prices and features checked Oct 16, 2026. I run Dataford. If something here is out of date, email me and I'll fix it.