SQL & Database Queries: Write a SQL query to find the second highest salary in a table. How would you optimize a slow-running SQL query? Explain the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN. How would you handle missing data in a database? Excel & Data Manipulation: How would you use a Pivot Table to summarize sales data? Explain the use of VLOOKUP and HLOOKUP in Excel. How do you apply conditional formatting in Excel based on specific criteria? Describe a situation where you used Excel to solve a complex data problem. Data Analysis & Visualization: How would you approach analyzing a dataset with millions of rows? What steps would you take to clean and preprocess a raw dataset? Explain the process of creating a dashboard in Power BI or Tableau. How do you choose the right chart type for different data sets? Statistical Analysis: Explain the difference between correlation and causation. How would you perform hypothesis testing? Can you explain the concepts of Type I and Type II errors? What is regression analysis, and when would you use it? How would you handle outliers in a dataset?
