10+ Interview Questions and Answers

Active and Passive transformation in Informatica and SQL query in a project

• Active transformation changes the number of rows that pass through it, while passive transformation does not

• Active transformation can change the data values, while passive transformation does not

• Examples of active transformation include Filter, Router, and Update Strategy, while passive transformation includes Expression and Sequence Generator

• SQL query in a project can be used to extract, manipulate, a...read more

The condition is that I have access to all necessary resources and support.

• Access to necessary resources such as tools, software, and data

• Support from team members and management

• Examples: access to testing environments, collaboration tools, training resources

Redux middleware is a function that intercepts actions and can modify or dispatch new actions.

• Middleware can be used for logging, error handling, and asynchronous actions.

• Syntax: const middleware = store => next => action => { //middleware logic }

• Redux selectors are functions that extract specific data from the Redux store.

• Example: const getUserName = state => state.user.name;

To delete duplicate records in SQL, use the DISTINCT keyword or GROUP BY clause.

• Use the DISTINCT keyword to select unique records and delete the duplicates.

• Use the GROUP BY clause to group records by a specific column and delete duplicates within each group.

• Use the HAVING clause to filter out groups with more than one record.

• Example: DELETE FROM table_name WHERE column_name NOT IN (SELECT MIN(column_name) FROM table_name GROUP BY duplicate_column);

Product launch impacts can be significant and far-reaching.

• Increased sales and revenue

• Brand recognition and awareness

• Market share growth

• Competitive advantage

• Customer satisfaction and loyalty

• Supply chain and logistics changes

• Employee morale and engagement

A billing system is a software application that manages and automates the billing process for products or services.

• A billing system generates invoices and tracks payments.

• It can integrate with other systems such as accounting software.

• It can also provide analytics and reporting on billing data.

• Examples include QuickBooks, FreshBooks, and Zoho Invoice.

Abstract class is a class that can have both abstract and non-abstract methods, while interface only has abstract methods.

• Abstract class can have constructors, while interface cannot

• A class can implement multiple interfaces, but can only inherit from one abstract class

• Abstract class can have instance variables, while interface cannot

• Abstract class is used when there is a need for a common base class for multiple related classes, while interface is used when there is a need fo...read more

String is immutable, while StringBuffer is mutable in Java.

• String is immutable, meaning once created, it cannot be changed. StringBuffer is mutable and can be modified.

• StringBuffer is synchronized, making it thread-safe. String is not synchronized.

• StringBuffer is more efficient for concatenating multiple strings due to its mutable nature.

• Example: String str = "Hello"; StringBuffer sb = new StringBuffer("Hello");

Optional class in Java 8 is used to represent a value that may or may not be present.

• Optional class helps to avoid NullPointerException by explicitly handling null values.

• It provides methods like isPresent(), ifPresent(), orElse() to work with optional values.

• Example: Optional optionalString = Optional.ofNullable("Hello");

Stream API in Java provides a way to process collections of objects in a functional style.

• Stream API allows for easy manipulation of collections using functional programming concepts like map, filter, and reduce.

• Streams can be created from various data sources like collections, arrays, or even I/O channels.

• Stream operations can be either intermediate (like filter or map) or terminal (like forEach or collect).