Riversand Technologies Interview Questions and Answers

To create a pipeline in Databricks, you can use Databricks Jobs or Apache Airflow for orchestration.

• Use Databricks Jobs to create a pipeline by scheduling notebooks or Spark jobs.

• Utilize Apache Airflow for more complex pipeline orchestration with dependencies and monitoring.

• Leverage Databricks Delta for managing data pipelines with ACID transactions and versioning.

An abstract class is a class that cannot be instantiated and may contain abstract methods that must be implemented by its subclasses.

• Cannot be instantiated directly

• May contain abstract methods

• Used as a blueprint for other classes

Abstraction is the process of hiding complex details and showing only the essential features of an object or system.

• Abstraction allows us to focus on what an object does, rather than how it does it

• It helps in simplifying complex systems by breaking them down into smaller, more manageable parts

• Examples of abstraction include using a car without needing to understand its internal combustion engine, or using a smartphone

QuickSort is one of the best sorting algorithms with an average time complexity of O(n log n).

• QuickSort is a divide and conquer algorithm that works by selecting a 'pivot' element and partitioning the array around the pivot.

• It has an average time complexity of O(n log n) and a worst-case time complexity of O(n^2).

• Example: ['apple', 'banana', 'cherry', 'date', 'fig'] can be sorted using QuickSort.

• Example: ['3', '1', '4'...read more

Bubble sorting has a time complexity of O(n^2) for a sorted list.

• Bubble sorting has a worst-case time complexity of O(n^2) for a sorted list.

• The time complexity does not change even if the list is already sorted.

• Example: If we have a sorted list of size n, bubble sorting will still take O(n^2) time.

Yes, I have been to multiple states other than Jharkhand.

• I have traveled to states like Maharashtra, Karnataka, and Tamil Nadu for work and leisure.

• I have visited tourist destinations in states like Rajasthan, Kerala, and Himachal Pradesh.

• I have family in states like Uttar Pradesh, Bihar, and West Bengal, which I have visited multiple times.

Reversing a linked list in Java using iterative approach.

• Create three pointers: prev, current, and next.

• Iterate through the list, updating pointers to reverse the links.

• Return the new head of the reversed list.

Handle StaleElementReferenceException by re-locating the element before interacting with it.

• Use try-catch block to catch StaleElementReferenceException

• Re-locate the element using findElement method before interacting with it

• Use WebDriverWait to wait for the element to become stale

I have worked on various projects involving test automation, performance testing, and quality assurance processes.

• Developed automated test scripts using Selenium WebDriver for web applications

• Conducted performance testing using JMeter to identify bottlenecks and optimize system performance

• Implemented quality assurance processes to ensure software meets requirements and standards

• Collaborated with cross-functional teams ...read more

My strategy for designing an automation framework involves identifying key functionalities, selecting appropriate tools, creating reusable components, implementing robust error handling, and integrating with CI/CD pipelines.

• Identify key functionalities to be automated based on priority and impact on testing.

• Select appropriate tools and technologies based on the application under test and team expertise.

• Create reusable ...read more

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

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.

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