SQL Practice Questions
Practice the most common SQL questions asked in data interviews!
Total Revenue per Customer
Count Orders per Day
Top 2 Products by Revenue per Category
Monthly Active Users (MAU)
Customers with More Than 2 Orders
Average Transaction Amount per Account
First Order Date per Customer
Orders Above Average Amount
Customers Without Any Orders
Most Recent Order per Customer
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About Noruj SQL Practice Sandbox
Welcome to the Noruj SQL Practice Platform, a comprehensive space created to help aspiring Data Analysts, Data Engineers, and Backend Developers test their SQL skills and prepare for technical interviews.
Curated Interview Questions
Tackle a carefully selected list of SQL problems sourced from real technical interviews at top tech companies. Ranging from basic SELECT statements to complex window functions.
In-Browser Execution
Write your solutions directly in our integrated SQL editor. No need to install PostgreSQL or import datasets; our browser-based engine compiles and evaluates your queries instantly.
Progress Tracking
Your progress is tracked and saved against your account. Track which challenges you've mastered, review your past solutions, and identify areas for improvement.
Real-time Feedback
Submit your queries and receive immediate feedback. Compare your output table with the expected results to understand edge cases and refine your logic.
Why Is SQL Critical for Interviews?
Structured Query Language (SQL) is the foundational tool for communicating with relational databases. Whether you are generating reports, analyzing consumer behavior, or building scalable backends, SQL remains the industry standard.
- Data Analytics: Clean, aggregate, and analyze data to extract actionable business insights.
- Backend Engineering: Perform efficient database transactions, handle concurrency, and model real-world domains.
- Data Engineering: Construct resilient ETL pipelines and optimize queries for large-scale data warehouses.
How to Use This Platform
- Choose a Problem: Use filters for Difficulty (Easy, Medium, Hard) or search by specific tags like "Joins", "Aggregations", or "Window Functions".
- Read the Prompt: Review the problem description and analyze the provided table schema and expected outcome.
- Write and Test: Craft your SQL query in the editor and hit "Run Query" to evaluate it against the sample database.
Ready to freely explore databases? Try our Free Online SQL Playground for unstructured practice and testing.