80+ Junior Software Engineer Interview Questions and Answers for Freshers

What is the probability of picking a red ball out of 10 balls with 2 red, 5 blue, and 3 orange?

• There are 2 red balls out of 10 total balls

• The probability of picking a red ball is 2/10 or 1/5

• The probability can also be expressed as 20%

RDBMS is a relational database management system. SQL query to retrieve data is SELECT * FROM table_name;

• RDBMS is a software system used to manage relational databases.

• SQL is a programming language used to manage RDBMS.

• SELECT statement is used to retrieve data from a table.

• The * symbol retrieves all columns from the specified table.

• table_name is the name of the table from which data is to be retrieved.

Stack memory is used for static memory allocation while heap memory is used for dynamic memory allocation.

• Stack memory is allocated at compile-time while heap memory is allocated at runtime.

• Stack memory is limited in size while heap memory can grow dynamically.

• Stack memory is automatically managed by the system while heap memory must be manually managed.

• Examples of stack memory include function call stack and local variables while examples of heap memory include objects creat...read more

Interview questions for Junior Software Engineer position covering OOP, HTML, SDLC, and programming logic.

• OOP stands for Object-Oriented Programming, with types including classes, objects, inheritance, polymorphism, and encapsulation.

• HTML tags are used to structure web pages, while null tag is not a valid HTML tag.

• SDLC stands for Software Development Life Cycle, with stages like planning, analysis, design, implementation, testing, and maintenance.

• Example of printing a pattern...read more

Active and passive transformations are methods used in data integration to transform data from one format to another.

• Active transformations are used to change the number of rows that pass through the transformation, such as filtering or sorting data.

• Passive transformations do not change the number of rows that pass through the transformation, such as changing data types or renaming columns.

• Examples of active transformations include Filter, Sorter, and Router transformations.

• E...read more

Exception handling is a mechanism to handle runtime errors and prevent program crashes.

• It allows the program to gracefully handle errors and continue execution.

• C does have a basic form of exception handling using the setjmp() and longjmp() functions.

• Examples of exceptions include divide by zero, null pointer dereference, and file not found errors.

Count the number of words in a user input string.

• Use the split() method to split the string into an array of words.

• Get the length of the array to get the number of words.

• Handle edge cases like leading/trailing spaces and multiple spaces between words.

Visualize data in Tableau using various charts and graphs.

• Select appropriate chart type based on data and analysis goal

• Use color, size, and shape to encode additional information

• Create interactive dashboards for exploration and analysis

• Utilize Tableau's built-in features such as filters and parameters

• Consider audience and design for effective communication

I am open to discussing the package and would like to know more about the benefits and growth opportunities.

• I am willing to negotiate based on the overall package, including benefits and growth opportunities.

• I would like to know more about the company culture and values.

• I am open to discussing the possibility of performance-based incentives.

• I am interested in opportunities for professional development and advancement.

• I would like to know more about the specific responsibiliti...read more

Find 3 indices whose values sum up to 0.

• Use nested loops to compare each index with every other index.

• Store the sum of each pair of indices in a hash table.

• Check if any three indices have a sum of 0.

Informatica is a data integration tool used for ETL (Extract, Transform, Load) processes.

• Used for data integration and ETL processes

• Can connect to various data sources and targets

• Provides a graphical interface for designing and managing workflows

• Supports scheduling and monitoring of workflows

• Can handle large volumes of data

• Examples of use cases include data warehousing, data migration, and data synchronization

let, const, and var are used to declare variables in JavaScript. Closures are functions that have access to their outer scope even after the outer function has finished executing.

• let: block-scoped variable declaration, can be reassigned

• const: block-scoped variable declaration, cannot be reassigned, but its properties can be modified

• var: function-scoped variable declaration, can be reassigned

• Closure: inner function has access to outer function's variables even after outer func...read more

Delegates are reference types that hold a reference to a method. They provide flexibility and extensibility in C#.

• Delegates allow methods to be passed as parameters to other methods.

• They can be used to implement callbacks and event handlers.

• Delegates can be chained together to create a pipeline of methods to be executed.

• They provide a way to decouple the caller from the implementation of a method.

• Delegates can be used to implement the observer pattern.

• Examples of delegates in...read more

Remove duplicates from an array of strings using various methods.

• Use a Set: Convert the array to a Set to automatically remove duplicates. Example: `const uniqueArray = [...new Set(array)];`

• Filter Method: Use `filter()` to keep only unique elements. Example: `const uniqueArray = array.filter((item, index) => array.indexOf(item) === index);`

• Reduce Method: Use `reduce()` to build a new array with unique values. Example: `const uniqueArray = array.reduce((acc, item) => acc.inclu...read more

Model is bound to controller in MVC through data binding techniques.

• Use data binding frameworks or libraries provided by the MVC framework.

• Define the model class and its properties in the controller.

• Map the model properties to the corresponding view elements.

• Update the model data in the controller based on user input or other events.

• Ensure proper synchronization between the model and the view.

The new keyword is used in object-oriented programming to create a new instance of a class or struct.

• Used to allocate memory for a new object

• Invokes the constructor of the class or struct

• Returns a reference to the newly created object

Exceptional handling is the process of identifying, catching, and responding to errors in software applications.

• Exception handling is used to prevent application crashes and provide a graceful way to handle errors.

• It involves using try-catch blocks to catch exceptions and handle them appropriately.

• Logging and reporting exceptions is also important for debugging and improving application performance.

• Best practices include using specific exception types, avoiding catching gener...read more

Object-oriented programming concepts focus on data and methods, including inheritance, encapsulation, polymorphism, and abstraction.

• Inheritance: Allows a class to inherit properties and behavior from another class.

• Encapsulation: Bundling data and methods that operate on the data into a single unit.

• Polymorphism: Ability to present the same interface for different data types.

• Abstraction: Hiding the complex implementation details and showing only the necessary features.

The super keyword is used in Java to refer to the immediate parent class object.

• Used to access methods and variables of the parent class

• Helps in achieving method overriding in inheritance

• Can be used to call the constructor of the parent class

• Example: super.methodName();

Joins are used in SQL to combine data from two or more tables based on a related column.

• Joins are used to retrieve data from multiple tables in a single query

• There are different types of joins such as inner join, left join, right join, and full outer join

• Joins are based on a related column between the tables

• Example: SELECT * FROM table1 INNER JOIN table2 ON table1.column = table2.column

Design includes elements such as layout, color, typography, and functionality.

• Layout

• Color

• Typography

• Functionality

Abstract class can have both abstract and non-abstract methods, while functional interface can have only one abstract method.

• Abstract class can have constructors, fields, and methods, while functional interface can only have one abstract method.

• Abstract class can have abstract and non-abstract methods, while functional interface can only have one abstract method.

• Abstract class can provide default implementations for methods, while functional interface cannot.

• Example: Abstract...read more

Dynamic method dispatch is a mechanism by which a call to an overridden method is resolved at runtime rather than compile time.

• In dynamic method dispatch, the actual method called is determined by the type of object at runtime.

• It allows for polymorphism in object-oriented programming languages.

• Example: Animal class with a method 'makeSound', and subclasses Dog and Cat that override 'makeSound'. Calling 'makeSound' on an Animal reference will execute the appropriate method bas...read more

Function to convert Roman numeral to integer

• Create a dictionary mapping Roman numerals to their integer values

• Iterate through the input Roman numeral string from right to left

• If current numeral value is less than the next numeral value, subtract it from the total

• Otherwise, add it to the total

• Return the total integer value

OOPs concepts include encapsulation, inheritance, polymorphism, and abstraction. Abstraction is a concept where only relevant information is shown to the user, while interface is a blueprint for classes.

• OOPs concepts: encapsulation, inheritance, polymorphism, abstraction

• Abstraction: showing only relevant information to the user

• Interface: blueprint for classes, defines methods without implementation

• Example: Abstraction - Car dashboard displaying speed without showing internal ...read more

Tableau is a powerful data visualization tool that helps in analyzing and presenting complex data in an easy-to-understand format.

• Allows creation of interactive dashboards and reports

• Enables quick and easy data exploration

• Provides real-time collaboration and sharing of insights

• Supports integration with various data sources

• Offers advanced analytics and predictive modeling capabilities

To reverse an array of numbers, iterate through the array and swap elements from start to end.

• Iterate through the array using two pointers, one starting from the beginning and the other from the end.

• Swap elements at the two pointers and move the pointers towards the center until they meet.

• Example: Input array [1, 2, 3, 4, 5], after reversing becomes [5, 4, 3, 2, 1].