Cognizant Technical Lead Interview Questions and Answers

A foreach loop iterates over elements in a collection, while a for loop uses an index to control iterations.

• Foreach loops are simpler and more readable for collections.

• For loops provide more control over the iteration process.

• Example of foreach: foreach (var item in collection) { /* code */ }

• Example of for: for (int i = 0; i < array.Length; i++) { /* code */ }

• Foreach cannot modify the collection during iteratio...read more

Disaster recovery strategies are plans to restore IT systems and data after a disruptive event, ensuring business continuity.

• Backup and Restore: Regularly back up data to recover from data loss. Example: Using cloud storage for backups.

• Failover: Automatically switch to a standby system in case of failure. Example: Using a secondary server for critical applications.

• Disaster Recovery as a Service (DRaaS): Outsourcin...read more

Effective logging is crucial for monitoring applications, debugging issues, and maintaining system health in software development.

• Log Levels: Use different log levels (e.g., DEBUG, INFO, WARN, ERROR) to categorize the importance of log messages, making it easier to filter logs.

• Structured Logging: Implement structured logging (e.g., JSON format) to make logs machine-readable and facilitate easier searching and anal...read more

In Databricks, you can pass values between notebooks using widgets, parameters, or by writing to a shared location.

• Widgets: Use Databricks widgets to create input fields in one notebook and retrieve their values in another. Example: dbutils.widgets.text('input', 'default')

• Notebook Parameters: Pass parameters when calling a notebook using the 'notebook' command. Example: dbutils.notebook.run('notebook_path', 60, {'...read more

Functional components are stateless components in React, while class components are stateful components.

• Functional components are simpler and easier to read/write compared to class components.

• Functional components do not have access to lifecycle methods or state, while class components do.

• Functional components are preferred for simple UI components, while class components are used for more complex components.

• Examp...read more

CTE stands for Common Table Expressions. It is a temporary result set that can be referenced within a SELECT, INSERT, UPDATE, or DELETE statement.

• CTE is defined using the WITH keyword in SQL.

• It helps in breaking down complex queries into simpler, more manageable parts.

• CTEs can reference themselves recursively, making them useful for hierarchical data.

• They are especially useful for avoiding code duplication and imp...read more