Backend Software Engineer Interview Questions and Answers

I would prefer using a relational database like PostgreSQL when starting the application.

• Relational databases provide strong consistency and ACID compliance

• PostgreSQL is open-source, widely used, and has a strong community support

• Supports complex queries and transactions

• Good performance for read-heavy applications

Error handling on sites involves logging, alerting, and gracefully handling errors to prevent user impact.

• Implement logging to track errors and monitor site performance.

• Set up alerts to notify the team immediately when errors occur.

• Provide users with informative error messages to guide them on next steps.

• Use try-catch blocks in code to gracefully handle errors and prevent crashes.

• Regularly review and update error handling processes to improve site reliability.

To start a chat application from scratch, you would need to design the architecture, choose the technology stack, implement user authentication, create messaging functionality, and deploy the application.

• Design the architecture of the application including database structure, server-client communication, and user interface.

• Choose the technology stack based on the requirements of the application, such as Node.js for backend, WebSocket for real-time communication, and React for...read more

Topological sort can be used to traverse an array of strings in a specific order.

• Topological sort is used to order elements based on their dependencies.

• In the context of array traversal, we can use topological sort to determine the order in which strings should be processed.

• For example, if strings represent tasks and their dependencies, we can use topological sort to ensure tasks are executed in the correct order.

To reverse a HashMap, create a new HashMap with keys and values swapped.

• Create a new HashMap to store the reversed key-value pairs.

• Iterate through the original HashMap and add each entry to the new HashMap with key and value swapped.

• Return the reversed HashMap.