Alaan Senior Software Engineer Interview Questions and Answers

Implement a caching service to store results of a method for specific inputs, avoiding redundant calculations.

• Use a dictionary to store cached results, e.g., cache = {}.

• Define a decorator function to wrap the target method, e.g., @cache_decorator.

• Check if the input exists in the cache before executing the method.

• If cached, return the cached result; otherwise, compute and store it.

• Example: sumOfArray([1, 2, 3]) -> 6,...read more

Use a distributed task scheduler like Apache Airflow to run cron jobs in parallel on multiple instances.

• Utilize a distributed task scheduler like Apache Airflow to manage and run cron jobs in parallel on multiple instances.

• Define tasks in Airflow DAGs to specify the jobs to be executed and their dependencies.

• Configure Airflow to distribute the tasks across multiple worker nodes for parallel execution.

• Monitor the execut...read more

JavaScript arrays are dynamic, allowing flexible size and mixed data types, differing from static arrays in many other languages.

• Dynamic Sizing: JavaScript arrays can grow and shrink in size dynamically. For example, let arr = []; arr.push('item');

• Mixed Data Types: Arrays in JavaScript can hold different types of data. For instance, let arr = [1, 'string', true];

• Array Methods: JavaScript provides numerous built-in meth...read more

To fetch the 2nd highest salary, use SQL queries with subqueries or the DISTINCT keyword.

• Use a subquery: SELECT MAX(salary) FROM employees WHERE salary < (SELECT MAX(salary) FROM employees);

• Use DISTINCT to eliminate duplicates: SELECT DISTINCT salary FROM employees ORDER BY salary DESC LIMIT 1 OFFSET 1;

• Consider using ROW_NUMBER() for more complex scenarios: SELECT salary FROM (SELECT salary, ROW_NUMBER() OVER (ORDER...read more