10+ EXL Service Data Analyst Interview Questions and Answers

Query to get number of matches played and won by each team from a table of match details.

• Use GROUP BY clause to group the data by team name.

• Use COUNT() function to get the number of matches played by each team.

• Use SUM() function with a condition to get the number of matches won by each team.

Python code to calculate factorial of a number.

• Use a loop to iterate from 1 to the given number.

• Multiply each number with the previous result.

• Return the final result.

HAVING is used with GROUP BY to filter groups, WHERE is used to filter rows

• HAVING is used with GROUP BY clause to filter the groups based on aggregate functions

• WHERE is used to filter rows based on conditions

• HAVING is applied after the GROUP BY clause, WHERE is applied before

• HAVING can only be used with SELECT statement that contains a GROUP BY clause

• Example: SELECT department, AVG(salary) FROM employees GROUP BY department HAVING AVG(salary) > 50000;

• Example: SELECT * FROM em...read more

Python strings are immutable, meaning they cannot be changed once created.

• Python strings are immutable, so any operation that appears to modify a string actually creates a new string object.

• For example, when you use string concatenation or slicing, a new string is created instead of modifying the original string.

• To modify a string in Python, you would need to create a new string with the desired changes.

Use Python's set() function to remove duplicate values from an array of strings.

• Convert the array to a set to automatically remove duplicates

• Convert the set back to a list if needed

Improving processes involves identifying inefficiencies, implementing changes, and continuously monitoring and adjusting for optimal results.

• Identify bottlenecks and areas of inefficiency

• Implement automation and technology solutions

• Streamline communication and collaboration between teams

• Regularly review and analyze data to identify areas for improvement

• Seek feedback from stakeholders and incorporate suggestions for enhancement

Negativity can be overcome by practicing gratitude, surrounding yourself with positive people, and focusing on solutions rather than problems.

• Practice gratitude by keeping a gratitude journal or regularly reflecting on things you are thankful for

• Surround yourself with positive people who uplift and support you

• Focus on solutions rather than dwelling on problems - brainstorming ways to address challenges can help shift your mindset

Use SQL query with ORDER BY and LIMIT to find 2nd highest salary

• Use ORDER BY clause to sort salaries in descending order

• Use LIMIT 1,1 to skip the highest salary and get the second highest

• Example: SELECT salary FROM employees ORDER BY salary DESC LIMIT 1,1

Use the concatenate function from numpy to merge two arrays in Python.

• Import numpy library

• Use np.concatenate() function to merge the arrays

• Ensure both arrays have the same data type

Running total in SQL is achieved by using window functions like SUM() with OVER() clause.

• Use SUM() function with OVER() clause to calculate running total.

• Specify the window frame with ORDER BY in the OVER() clause.

• Running total can be reset based on certain conditions using PARTITION BY in the OVER() clause.

Functions in SQL and Excel are used to perform calculations, manipulate data, and automate tasks.

• Functions in SQL are used to perform calculations, manipulate data, and automate tasks within a database.

• Common SQL functions include SUM, AVG, COUNT, MAX, MIN, and CONCAT.

• Functions in Excel are used to perform calculations, manipulate data, and automate tasks within spreadsheets.

• Common Excel functions include SUM, AVERAGE, IF, VLOOKUP, and CONCATENATE.

Use the sorted() function to sort an array of strings in Python.

• Use the sorted() function with the array as input to get a new sorted array.

• You can use the reverse parameter to sort in descending order.

• You can use the key parameter to specify a custom sorting key.

• Example: sorted_array = sorted(array)