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Query Databases Like a Senior Engineer

Master SQL in One Weekend (While Your Competitors Struggle for Months)

Learn the exact SQL patterns used to query millions of rows at Amazon, Netflix, and Stripe. Get hired faster with portfolio-ready projects.

Avg. completion: 2-3 days
Interactive: Hands-on exercises
AI Tutor: Get unstuck 24/7

Start Learning SQL Free

100% Free. No Credit Card. Query Real Databases in Minutes.

100% Free to start. No credit card. No trial. Just value.
Start in 30 seconds. No downloads. No setup. Learn in your browser.
Keep your progress. Pick up where you left off, anytime.

100% free to start. Cancel anytime.
You have nothing to lose and everything to gain.

2 days
Completion Time
50+
Practice Queries
5
Real Datasets
$15K
Average Salary Increase

Sound Familiar?

If you're struggling with any of these, you're in the right place:

Writing slow queries that take 10+ seconds (and getting complaints from users)

JOINs still confuse you (LEFT vs RIGHT vs INNER... which one?)

Can't optimize queries—just hoping the database is fast enough

Scared to touch production data (what if you accidentally DELETE everything?)

Here's the truth: It's not your fault.

Most tutorials teach theory. We teach the exact patterns used in production by companies like Google, Meta, and Stripe. That's why our students get results 10x faster.

What You'll Master

Concrete skills you'll walk away with (not vague promises):

Write complex JOINs in 60 seconds (without Googling)

Optimize queries to run 10x-100x faster

Analyze data to make business decisions worth $100K+

Ace SQL interview questions from FAANG companies

Build dashboards that impress your boss

The Complete Roadmap

Everything broken down into bite-sized, actionable steps:

1

SQL Fundamentals (Day 1)

Master SELECT, WHERE, and the mental model of tables

  • SELECT queries: filtering, sorting, limiting results
  • WHERE clauses: comparison operators and logical conditions
  • Aggregate functions: COUNT, SUM, AVG, MIN, MAX
  • GROUP BY and HAVING: summarizing data like a pro
2

JOINs & Relationships (Day 2 Morning)

Combine data from multiple tables confidently

  • INNER JOIN: get matching records
  • LEFT/RIGHT JOIN: include all records from one side
  • Multiple JOINs: combining 3+ tables
  • Subqueries vs JOINs: when to use each
3

Advanced Patterns (Day 2 Afternoon)

Window functions, CTEs, and performance optimization

  • Window functions: ROW_NUMBER, RANK, LAG, LEAD
  • Common Table Expressions (CTEs): readable complex queries
  • Indexes: make queries 100x faster
  • Query execution plans: debug slow queries

Ready to Level Up?

Start learning with hands-on exercises and an AI tutor available 24/7.

Avg. completion: 2-3 days
Interactive: Hands-on exercises
AI Tutor: Get unstuck 24/7

Start Learning SQL Free

100% Free. No Credit Card. Query Real Databases in Minutes.

100% Free to start. No credit card. No trial. Just value.
Start in 30 seconds. No downloads. No setup. Learn in your browser.
Keep your progress. Pick up where you left off, anytime.

100% free to start. Cancel anytime.
You have nothing to lose and everything to gain.

Common Questions

Is this really free?

Yes. 100% free to start. No credit card required. No trial period. You get instant access to the full curriculum. We make money from premium features (AI tutoring, certifications) but the core learning is always free.

How long will this take?

Most students complete this roadmap in 2 days. But you can go at your own pace. Some finish in a weekend sprint. Others take a few weeks while working full-time. The platform tracks your progress so you never lose your place.

What if I get stuck?

Every exercise includes an AI tutor trained on the course content. It provides progressive hints without spoiling the solution, helping you learn by discovery rather than by copying answers.

I'm a complete beginner. Will I understand this?

Absolutely. We start from zero. No prior knowledge required. Every concept is explained with analogies, visuals, and real-world examples. If you can use a computer, you can learn this.

Will this help me get a job?

Yes. These are the exact skills listed in job descriptions from Google, Meta, startups, and agencies. You'll build portfolio projects you can show to employers. Our students have gotten offers from companies like Shopify, Stripe, and Y Combinator startups.

Still Reading?

You've made it this far. That means you're serious about leveling up.
The only question left is: Will you take action?

The best time to start was yesterday.
The second best time is right now.