200+ Junior Software Engineer Interview Questions and Answers

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

Infotainment system is a combination of information and entertainment features in a car.

• It includes features like audio and video playback, navigation, climate control, and connectivity options.

• Examples of infotainment systems are Apple CarPlay, Android Auto, and Ford SYNC.

• It enhances the driving experience by providing entertainment and information to the driver and passengers.

Angular is a popular front-end framework, hooks are functions that let you use state and other React features in functional components, closures are functions that retain access to variables in their lexical scope, promises are objects representing the eventual completion or failure of an asynchronous operation, async/await is a way to write asynchronous code that looks synchronous, @Input and @Output are decorators used for communication between parent and child components i...read more

CIDR block is a method of allocating IP addresses and routing Internet Protocol packets.

• CIDR stands for Classless Inter-Domain Routing.

• It is used to allocate IP addresses and route Internet Protocol packets.

• CIDR block is a combination of an IP address and its associated network mask.

• CIDR notation is used to represent the CIDR block, for example, 192.168.0.0/16.

• The range of CIDR block varies depending on the network mask used.

Class is a blueprint for creating objects, interface defines a contract for classes, abstract class cannot be instantiated, dependency injection is a design pattern for injecting dependencies into a class.

• Class is a template for creating objects with properties and methods.

• Interface defines a set of methods that a class must implement.

• Abstract class cannot be instantiated and can have abstract methods that must be implemented by subclasses.

• Dependency injection is a design pat...read more

Code for Fibonacci series up to 10

• Declare two variables to store the first two numbers of the series

• Use a loop to generate the next numbers in the series by adding the previous two

• Print the series up to 10

C# program to return sum of values passed through a list of numbers as a parameter.

• Create a method that takes a list of numbers as a parameter

• Use a loop to iterate through the list and add each number to a sum variable

• Return the sum variable

The jar is half full in the 15th second.

• The bacteria double every second, so the jar is half full in the second before it is full.

• Since the jar is full in the 16th second, it must be half full in the 15th second.

DELETE

• GET

• POST

• PUT

• DELETE

Yes, I have completed a project on predicting customer churn using machine learning algorithms.

• Developed a predictive model using Python and scikit-learn

• Performed data preprocessing, feature engineering, and model evaluation

• Achieved an accuracy of 85% in predicting customer churn

• Used decision trees, random forests, and logistic regression for modeling

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

Code for Fibonacci series in Python.

• Use a loop to iterate through the series

• Start with 0 and 1 as the first two numbers

• Add the previous two numbers to get the next number

• Repeat until desired number of terms is reached

Indexing is a way to improve database performance by creating a separate data structure that allows faster data retrieval.

• Clustered index: sorts and stores the data rows in the table based on their key values

• Non-clustered index: creates a separate structure that includes the indexed columns and a pointer to the data row

• Full-text index: enables full-text search on character-based data types

• Filtered index: indexes a subset of data based on a filter predicate

• Spatial index: optim...read more

The @Html helper in ASP.NET MVC is used to generate HTML controls in a strongly-typed manner.

• Generates HTML controls based on the model properties

• Helps in maintaining type safety and reducing errors

• Provides a convenient way to create form elements and links

• Can be used for rendering partial views and displaying data

The correct syntax for defining a route in ASP.NET MVC involves using the Route attribute above the controller action method.

• Use the Route attribute above the controller action method to define a custom route

• Specify the route template within the Route attribute

• Example: [Route("custom/route")] public ActionResult MyAction() { }

Yes, we can delete records from views. Views are virtual tables that display data from one or more tables.

• Views are used to simplify complex queries by providing a virtual table with a specific subset of data.

• Deleting records from a view will delete the corresponding records from the underlying table(s).

• Views can also be used to restrict access to sensitive data by only allowing certain columns to be displayed.

• Example: DELETE FROM my_view WHERE column_name = 'value';

To check the data area value in AS400, you can use the DSPDTAARA command.

• Use the DSPDTAARA command followed by the library and data area name to display the value.

• You can also use the RTVDTAARA command to retrieve the value into a program variable.

• If the data area is in a different library, specify the library name before the data area name.

• Ensure that you have the necessary authority to access the data area.

To download files from AS400 system, use FTP or a file transfer utility like IBM i Access Client Solutions.

• Use FTP (File Transfer Protocol) to transfer files from AS400 system to another system.

• Install and configure an FTP client on your local machine.

• Connect to the AS400 system using the FTP client.

• Navigate to the directory where the files are located on the AS400 system.

• Use the 'get' command to download the files to your local machine.

• Alternatively, you can use a file trans...read more

To make a job run from one jobq to another, you can use the CHGJOBQ command in IBM i (AS/400) system.

• Use the CHGJOBQ command to change the job queue of a job

• Specify the new job queue name in the JOBQ parameter of the CHGJOBQ command

• The job will be moved to the specified job queue when it is next eligible to run

There are two types of job schedulers in AS400: the native job scheduler and the advanced job scheduler.

• The native job scheduler is the default scheduler provided by AS400.

• It allows scheduling jobs based on time, date, and other criteria.

• The advanced job scheduler is a third-party tool that offers more advanced scheduling capabilities.

• It provides features like dependency management, event-based scheduling, and workload balancing.

• Examples of advanced job schedulers for AS400 i...read more

Polymorphism is the ability of an object to take on many forms. It allows objects of different classes to be treated as if they were of the same class.

• Polymorphism is achieved through method overriding and method overloading.

• Method overriding is when a subclass provides a specific implementation of a method that is already provided by its parent class.

• Method overloading is when a class has two or more methods with the same name but different parameters.

• Example: A shape class ...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.

Query for fetching the second highest salary from a table.

• Use ORDER BY and LIMIT to fetch the second highest salary.

• Exclude the highest salary using subquery or WHERE clause.

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.

To swap two numbers, store one number in a temporary variable, assign the value of the second number to the first, and then assign the value of the temporary variable to the second.

• Declare two variables to store the numbers

• Assign values to the variables

• Declare a third variable to store the temporary value

• Assign the value of the first variable to the third variable

• Assign the value of the second variable to the first variable

• Assign the value of the third variable to the second ...read more

Types of joins in SQL include inner join, outer join, left join, and right join.

• Inner join: returns rows when there is a match in both tables

• Outer join: returns all rows when there is a match in one of the tables

• Left join: returns all rows from the left table and the matched rows from the right table

• Right join: returns all rows from the right table and the matched rows from the left table

To check source object in AS400, use the DSPOBJD command.

• Use the DSPOBJD command followed by the library name and object name to display object details.

• The source object type should be specified as *PGM or *FILE.

• The output will include information like source file, member, and source type.

HTML5 is the latest version of HTML used for structuring and presenting content on the web.

• HTML5 provides new semantic elements for better structuring of web pages.

• It supports multimedia elements like audio and video without the need for plugins.

• HTML5 introduces new APIs for offline web applications and improved browser compatibility.

• It enables better accessibility and mobile device support.

• HTML5 allows for more interactive and dynamic web applications through JavaScript APIs...read more

Use Floyd's Cycle Detection Algorithm to detect two loops in a linked list.

• Initialize two pointers, slow and fast, both starting at the head of the linked list.

• Move slow pointer by one step and fast pointer by two steps in each iteration.

• If they meet at some point, there is a loop. Reset one pointer to head and move both by one step until they meet again to find the start of the loop.

C# program to reverse a string and check if it is a palindrome.

• Declare a string variable and initialize it with the input string

• Convert the string to a character array

• Reverse the character array using Array.Reverse() method

• Convert the character array back to string

• Compare the reversed string with the original string to check if it is a palindrome

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

To insert data in AS400, use SQL INSERT statement with appropriate table name and column values.

• Connect to AS400 database using JDBC or ODBC driver

• Construct an SQL INSERT statement with the table name and column names

• Provide the values to be inserted for each column in the VALUES clause

• Execute the INSERT statement using a prepared statement or statement object

I deal with negativity by focusing on solutions and maintaining a positive attitude.

• I try to understand the root cause of the negativity and address it

• I surround myself with positive people and seek their support

• I practice mindfulness and meditation to stay calm and centered

• I focus on finding solutions rather than dwelling on the problem

• I maintain a positive attitude and try to see the silver lining in every situation

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

Program to append a string at the middle of another string

• Find the middle index of the original string

• Use string slicing to split the original string into two parts

• Concatenate the first part, new string, and second part to form the final string

Query to select sum of salaries department wise

• Use GROUP BY clause to group salaries by department

• Use SUM() function to calculate the sum of salaries

• Join the employee and department tables on department ID

Methods in collections are used to manipulate and retrieve data from collections in programming.

• Some common methods include add(), remove(), contains(), size(), and clear().

• For example, the add() method is used to add an element to a collection, while remove() is used to remove an element.

• The contains() method is used to check if a collection contains a specific element, while size() returns the number of elements in the collection.

• Finally, the clear() method is used to remov...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.

Call by value passes a copy of the variable's value, while call by reference passes a reference to the variable.

• Call by value passes the actual value of the variable being passed to a function.

• Call by reference passes a reference (memory address) of the variable being passed to a function.

• Changes made to the parameter in call by value do not affect the original variable, while changes in call by reference do.

Tableau was preferred due to its ease of use and better visualization capabilities.

• Tableau has a more user-friendly interface compared to Power BI.

• Tableau offers better visualization options and allows for more customization.

• Tableau has a larger community and more resources available for support.

• Power BI is more suitable for data modeling and analysis.

• The decision to use Tableau over Power BI was based on the specific needs of the project.

Microservices are a software development technique where applications are composed of small, independent services that communicate with each other.

• Microservices break down applications into smaller, loosely coupled services

• Each service is responsible for a specific function and can be developed, deployed, and scaled independently

• Communication between services is typically done through APIs

• Examples include Netflix, Amazon, and Uber which use microservices architecture

C++ is a compiled language with pointers and memory management, while Java is an interpreted language with garbage collection.

• C++ is faster and more memory-efficient than Java.

• Java is platform-independent, while C++ is not.

• C++ allows for manual memory management with pointers, while Java has automatic garbage collection.

• Java has a simpler syntax and is easier to learn than C++.

• C++ is commonly used for system-level programming, while Java is used for web and mobile application...read more

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

Routing in ASP.NET MVC is used to map incoming browser requests to specific controller actions.

• Routing helps in defining URL patterns and mapping them to controller actions.

• It allows for creating clean and user-friendly URLs.

• Routing also enables parameter passing in URLs for dynamic content.

• Example: RouteConfig.cs file in ASP.NET MVC project defines the routing configuration.

An array is a data structure that stores a collection of elements of the same type. It allows for easy access and manipulation of data.

• Arrays are declared by specifying the data type of the elements and the size of the array.

• For example, to declare an array of strings in C++, you would write: string myArray[5];

• Arrays can be accessed using index values, starting from 0.

• Elements in an array can be modified or accessed using their respective index values.