Databases10 lessons31 quiz questions
SQL
20-hour Pareto plan for SQL mastery targeting backend development and data engineering roles. Covers the queries and concepts that appear in 90% of real-world use and technical interviews.
What You Will Learn
- ✓SQL Mental Model: Relational Algebra and Execution Order
- ✓JOINs: Inner, Outer, Self, and Cross
- ✓Aggregation, GROUP BY, and HAVING
- ✓Subqueries and CTEs
- ✓Window Functions
- ✓Data Modification: INSERT, UPDATE, DELETE, and Transactions
- ✓Schema Design and Normalization
- ✓Indexes and Query Optimization
- ✓Advanced SQL: JSON, Array Operations, and Full-Text Search
- ✓Capstone: Real-World SQL Interview Problems
Overview
20-hour Pareto plan for SQL mastery targeting backend development and data engineering roles. Covers the queries and concepts that appear in 90% of real-world use and technical interviews.
SQL
SQL is tested in every backend and data engineering interview. Master JOINs, window functions, and query optimization.
JOINs
Window Functions
CTEs (Common Table Expressions)
Interview Tip
"Window functions (RANK, LAG, running totals) separate senior from junior SQL developers. Practice them on LeetCode Database problems."
Java Implementation — JDBC
Python Implementation
Sample Quiz Questions
1. What is the difference between WHERE and HAVING?
Understand·Difficulty: 2/5
2. What does LEFT JOIN return when there is no matching row in the right table?
Remember·Difficulty: 1/5
3. Write a SQL query to find the second-highest salary.
Apply·Difficulty: 3/5
+ 28 more questions available in the full app.
Related Topics
Master SQL for Your Next Interview
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