Post #2669

🎯📊 DATA ANALYST MOCK INTERVIEW (WITH ANSWERS) 🧠1️⃣ Tell me about yourself ✅ Sample Answer: “I have around 3 years of experience working with data. My core skills include SQL, Excel, and Power BI. I regularly work with data cleaning, transformation, and building dashboards to generate business insights. Recently, I’ve also been strengthening my Python skills for data analysis. I enjoy solving business problems using data and presenting insights in a simple and actionable way.” 📊2️⃣ What is the difference between WHERE and HAVING? ✅ Answer: WHERE filters rows before aggregation HAVING filters after aggregation Example: SELECT department, COUNT(*) FROM employees GROUP BY department HAVING COUNT(*) > 5; 🔗3️⃣ Explain different types of JOINs ✅ Answer: INNER JOIN → only matching records LEFT JOIN → all left + matching right RIGHT JOIN → all right + matching left FULL JOIN → all records from both 👉 In analytics, LEFT JOIN is most used. 🧠4️⃣ How do you find duplicate records in SQL? ✅ Answer: SELECT column, COUNT(*) FROM table GROUP BY column HAVING COUNT(*) > 1; 👉 Used for data cleaning. 📈5️⃣ What are window functions? ✅ Answer: “Window functions perform calculations across rows without reducing the number of rows. They are used for ranking, running totals, and comparisons.” Example: SELECT salary, RANK() OVER(ORDER BY salary DESC) FROM employees; 📊6️⃣ How do you handle missing data? ✅ Answer: Remove rows (if small impact) Replace with mean/median Use default values Use interpolation (advanced) 👉 Depends on business context. 📉7️⃣ What is the difference between COUNT(_) and COUNT(column)? ✅ Answer: COUNT(*) → counts all rows COUNT(column) → ignores NULL values 📊8️⃣ What is a KPI? Give example ✅ Answer: “KPI (Key Performance Indicator) is a measurable value used to track performance.” Examples: Revenue growth, Conversion rate, Customer retention 🧠9️⃣ How would you find the 2nd highest salary? ✅ Answer: SELECT MAX(salary) FROM employees WHERE salary < ( SELECT MAX(salary) FROM employees ); 📊🔟 Explain your dashboard project ✅ Strong Answer: “I created a sales dashboard in Power BI where I analyzed revenue trends, top-performing products, and regional performance. I used DAX for calculations and added filters for better interactivity. This helped stakeholders identify key areas for growth.” 🔥1️⃣1️⃣ What is normalization? ✅ Answer: “Normalization is the process of organizing data to reduce redundancy and improve data integrity.” 📊1️⃣2️⃣ Difference between INNER JOIN and LEFT JOIN? ✅ Answer: INNER JOIN → only matching data LEFT JOIN → keeps all left table data 👉 LEFT JOIN is preferred in analytics. 🧠1️⃣3️⃣ What is a CTE? ✅ Answer: “A CTE (Common Table Expression) is a temporary result set defined using WITH clause to improve readability.” 📈1️⃣4️⃣ How do you explain insights to non-technical people? ✅ Answer: “I focus on storytelling. Instead of technical terms, I explain insights in simple business language with visuals and examples.” 📊1️⃣5️⃣ What tools have you used? ✅ Answer: SQL, Excel, Power BI, Python (basic/advanced depending on you) 💼1️⃣6️⃣ Behavioral Question: Tell me about a challenge ✅ Answer: “While working on a dataset, I found inconsistencies in data. I cleaned and standardized it using SQL and Excel, ensuring accurate analysis. This improved the dashboard reliability.” Double Tap ♥️ For More