Nineleaps Technology Solutions Interview Questions and Answers

Q1. Coalesce, SQL Order of Execution
Add your answer
Q2. Given a table with fields(id, name, salary, managerId) find out the managers who have atleast 5 reportees under him/her.
Ans. 
Use SQL query to count number of reportees for each manager and filter out those with atleast 5 reportees.
• Write a SQL query to count number of reportees for each manager using GROUP BY clause

• Add HAVING clause to filter out managers with atleast 5 reportees

• Example: SELECT managerId, COUNT(id) AS num_reportees FROM table_name GROUP BY managerId HAVING num_reportees >= 5
Answered by AI
Add your answer
Q3. How to manage large datasets in python
Ans. 
Use libraries like pandas and dask to efficiently manage large datasets in Python.
• Use pandas library for data manipulation and analysis.

• Use dask library for parallel computing and out-of-core processing.

• Optimize memory usage by loading data in chunks or using data types efficiently.

• Consider using cloud services like AWS S3 or Google BigQuery for storing and processing large datasets.
Answered by AI
Add your answer
Q4. Name few of the commonly used python libraries used by DA
Ans. 
Some commonly used Python libraries for Data Analysts are Pandas, NumPy, Matplotlib, and Scikit-learn.
• Pandas - used for data manipulation and analysis

• NumPy - used for numerical computing and working with arrays

• Matplotlib - used for data visualization

• Scikit-learn - used for machine learning and data mining
Answered by AI
Add your answer

It wa really a great experience.

It was really a great experience.

Q1. Where do you see yourself after 3 years?
Ans. 
In 3 years, I see myself leading a team of data engineers, implementing cutting-edge technologies, and driving impactful data-driven decisions.
• Leading a team of data engineers

• Implementing cutting-edge technologies

• Driving impactful data-driven decisions
Answered by AI
Add your answer
Q2. What are your strenghts?
Ans. 
My strengths include strong analytical skills, attention to detail, and the ability to work well in a team.
• Strong analytical skills - able to analyze complex data sets and derive meaningful insights

• Attention to detail - meticulous in ensuring data accuracy and quality

• Team player - collaborate effectively with colleagues to achieve common goals
Answered by AI
Add your answer

Q1. What projects you have worked upon?
Ans. 
I have worked on projects involving building data pipelines, optimizing database performance, and creating machine learning models.
• Built data pipelines using Apache Spark and Kafka

• Optimized database performance by tuning queries and indexes

• Created machine learning models for predictive analytics

• Implemented real-time data processing using technologies like Apache Flink
Answered by AI
Add your answer
Q2. What is your CGPA?
Ans. 
My CGPA is 3.8 out of 4.0.
• My CGPA is 3.8, which is considered high in my university.

• I have consistently maintained a high CGPA throughout my academic career.

• I have received several academic awards based on my CGPA.

• My CGPA reflects my dedication and hard work towards my studies.
Answered by AI
Add your answer
Q3. What are your hobbies?
Ans. 
My hobbies include hiking, photography, and playing the guitar.
• Hiking: I enjoy exploring nature trails and challenging myself physically.

• Photography: I love capturing moments and landscapes through my camera lens.

• Playing the guitar: I find relaxation and creativity in strumming chords and learning new songs.
Answered by AI
Add your answer

Q1. Asked about coalese in sql and its syntax.
Ans. 
COALESCE in SQL returns the first non-null value from a list of arguments.
• Syntax: COALESCE(value1, value2, ..., valueN)

• Example: COALESCE(NULL, 'Hello', 'World') returns 'Hello'.

• Useful for handling NULL values in queries.

• Can be used in SELECT statements, WHERE clauses, and more.
Answered by AI
Add your answer
Q2. Sql from leetcode on windows function and joins and cte
Ans. 
Understanding SQL with Windows functions, joins, and CTEs is crucial for data analysis tasks.
• Windows functions allow you to perform calculations across a set of table rows related to the current row, e.g., ROW_NUMBER().

• Joins combine rows from two or more tables based on a related column, e.g., INNER JOIN, LEFT JOIN.

• Common Table Expressions (CTEs) simplify complex queries by breaking them into manageable parts, e.g., WI...read more
Answered by AI
Add your answer

Q1. Difference Between Union and Union All
Add your answer
Q2. SQL Execution order
Add your answer
Q3. Coalesce function in SQL
Ans. 
Coalesce function in SQL is used to return the first non-null value in a list of expressions.
• Coalesce function takes multiple parameters and returns the first non-null value.

• It is commonly used to handle null values in SQL queries.

• Example: SELECT COALESCE(column_name, 'N/A') FROM table_name;
Answered by AI
Add your answer