300+ Software Engineer Trainee Interview Questions and Answers

Answering questions related to software engineering concepts and database management systems.

• OOPs is a programming paradigm that focuses on objects and their interactions.

• The four pillars of OOPs are encapsulation, inheritance, polymorphism, and abstraction.

• Polymorphism allows objects of different types to be treated as objects of a common type.

• Method overloading is having multiple methods with the same name but different parameters.

• Method overriding is having a method in a s...read more

This interview question covers various topics in Java programming, including OOP concepts, inheritance, keywords, and implementing mathematical algorithms.

• OOP concepts include encapsulation, inheritance, polymorphism, and abstraction.

• Inheritance allows a class to inherit properties and methods from another class.

• To prevent inheritance in Java, use the 'final' keyword before the class declaration.

• Sealed, final, and static are keywords in Java with different functionalities.

• Imp...read more

No, we cannot create two columns with the same name in a relational table.

• Relational databases enforce uniqueness of column names within a table.

• Having two columns with the same name would lead to ambiguity and confusion.

• Column names are used to uniquely identify and access data in a table.

• If two columns have the same name, it would be impossible to distinguish between them.

• To avoid this, column names must be unique within a table.

Bought a pen for 50rs and sold it for 60rs. What is the percentage of profit or loss?

• Profit = Selling Price - Cost Price

• Profit = 60 - 50 = 10

• Profit Percentage = (Profit / Cost Price) * 100

• Profit Percentage = (10 / 50) * 100 = 20%

• Therefore, the percentage of profit is 20%

Answers to common interview questions for Software Engineer Trainee position.

• OOPS concept is a programming paradigm that focuses on objects and their interactions.

• Arrays are a collection of elements of the same data type, while stacks and linked lists are dynamic data structures.

• Linear data structures have a sequential order, while non-linear data structures do not.

• Be prepared to code on some questions, practice coding problems beforehand.

To remove redundancy in a database with repeated names, use normalization techniques.

• Identify the primary key of the table and ensure it is unique

• Create separate tables for related data to avoid repeating information

• Use foreign keys to link related tables

• Consider using indexing to improve performance

• Update existing data to conform to the new structure

Java is a high-level, object-oriented programming language that is platform-independent and widely used for developing applications, websites, and games.

• Developed by Sun Microsystems

• Collection of objects

• High performance and multi-threaded

• Used for developing Android apps, enterprise applications, and web applications

The question covers topics like two's complement, data structures, machine learning, and OOPs concepts in Java.

• Two's complement of a number 1001 is -0111.

• Data structures are ways of organizing and storing data in a computer so that it can be accessed and used efficiently. Examples include arrays, linked lists, stacks, queues, trees, and graphs.

• Machine learning is a subset of artificial intelligence that involves training algorithms to make predictions or decisions based on da...read more

Typecasting is used to convert one datatype into another.

• Typecasting is the process of converting a value from one datatype to another.

• It can be done implicitly or explicitly.

• Implicit typecasting is done automatically by the compiler.

• Explicit typecasting is done manually by the programmer using casting operators.

• Examples of typecasting include converting an integer to a float, a string to an integer, etc.

Call by value and reference are two ways of passing arguments to functions.

• Call by value passes a copy of the argument's value to the function.

• Call by reference passes a reference to the argument's memory location to the function.

• Functions that use call by value cannot modify the original value of the argument.

• Functions that use call by reference can modify the original value of the argument.

• In some programming languages, call by reference is achieved using pointers.

• Example: ...read more

Stress is the force applied to an object, while strain is the deformation caused by that force.

• Stress is measured in units of force per unit area, such as pounds per square inch (psi) or newtons per square meter (N/m²).

• Strain is a dimensionless quantity, typically expressed as a percentage or decimal, and is calculated as the change in length or shape divided by the original length or shape.

• Stress and strain are related by a material's modulus of elasticity, which describes h...read more

To print a statement in Python, use the print() function.

• Use the print() function followed by the statement you want to print.

• Enclose the statement in quotes if it is a string.

• You can also print variables or expressions by separating them with commas.

• To print multiple statements on the same line, use the end parameter.

I am comfortable with Java and Python.

• Proficient in Java and Python programming languages

• Experience in developing web applications using Java frameworks like Spring and Hibernate

• Familiar with Python libraries like NumPy and Pandas for data analysis

• Comfortable with object-oriented programming concepts and design patterns

Develop a 'To Do List' application with modern design and functionality like 'Add', 'Edit', 'Delete', and 'View List' within ½ hour.

• Use HTML, CSS, and JavaScript for front-end development

• Implement CRUD operations for tasks (Create, Read, Update, Delete)

• Design a user-friendly interface with header and footer

• Utilize localStorage or backend server for data storage

Answering questions related to programming languages, OOP, SQL queries, and easy level coding.

• I am proficient in Java and Python.

• The four pillars of OOP are encapsulation, inheritance, abstraction, and polymorphism.

• SQL queries involve selecting, inserting, updating, and deleting data from a database.

• I am comfortable with easy level coding challenges such as implementing basic algorithms or solving simple problems.

Answers to interview questions for Software Engineer Trainee

• Primary foreign key is a column in a table that is used to link to the primary key of another table

• ACID properties are Atomicity, Consistency, Isolation, and Durability which ensure database transactions are reliable

• To return 3rd maximum salary, use the LIMIT and OFFSET clauses in SQL

• SQL join is used to combine data from two or more tables based on a related column

• IN in SQL is used to specify multiple values in a WHE...read more

Interview questions for Software Engineer Trainee position

• Introduction should include name, education, and relevant experience

• Encapsulation is a mechanism to hide data and methods from outside world

• Inheritance is achieved by extending a class and using 'extends' keyword

• Collection frameworks in Java provide classes and interfaces to store and manipulate groups of objects

• Examples of collection frameworks include ArrayList, LinkedList, HashSet, and HashMap

Hooks are functions that allow us to use state and other React features in functional components.

• useState is a hook that allows us to add state to functional components.

• useRef is a hook that allows us to create a mutable reference that persists across renders.

• useEffect is a hook that allows us to perform side effects in functional components.

• useState example: const [count, setCount] = useState(0);

• useRef example: const inputRef = useRef(null);

• useEffect example: useEffect(() =>...read more

Answers to questions asked in a Software Engineer Trainee interview

• 4 pillars of OOPS: Abstraction, Encapsulation, Inheritance, Polymorphism

• Normalization types: 1NF, 2NF, 3NF, BCNF

• Heap tree: complete binary tree, used in heap sort, priority queue

• Quick sort: divide and conquer, worst case O(n^2), best case O(nlogn)

• Merge sort: divide and conquer, always O(nlogn)

• Join types: inner, outer, left, right

• Class and constructor can be made private

• Method is used to perform an action, cons...read more

Array list is a dynamic array that can grow or shrink in size, while array has a fixed size.

• Array list can dynamically resize itself, while array has a fixed size.

• Array list is part of Java's Collection framework, while array is a basic data structure in most programming languages.

• Array list allows insertion and deletion of elements at any position, while array does not support this flexibility.

A database is a structured collection of data that is organized and stored for easy access, retrieval, and management.

• A database is used to store and manage large amounts of data.

• It provides a way to organize and structure data for efficient storage and retrieval.

• Databases can be relational, object-oriented, or hierarchical, depending on the data model used.

• Examples of databases include MySQL, Oracle, MongoDB, and SQLite.

SLK stands for Software Load and Performance Testing. It is a process of testing software applications to ensure their performance under expected load.

• SLK is used to identify performance bottlenecks and optimize software applications.

• It involves simulating real-world scenarios and measuring the response time and resource usage.

• SLK helps in determining the maximum capacity of a software system and ensuring its stability.

• Examples of SLK tools include JMeter, LoadRunner, and Gat...read more

Binary search is better for sorted arrays. Time complexity: Linear - O(n), Binary - O(log n).

• Linear search is suitable for unsorted arrays.

• Binary search is suitable for sorted arrays.

• Linear search has a time complexity of O(n).

• Binary search has a time complexity of O(log n).

Waterfall model is a linear sequential approach, while incremental model divides the project into small increments.

• Waterfall model follows a linear and sequential approach, where each phase must be completed before moving on to the next.

• Incremental model divides the project into small increments, with each increment building upon the previous one.

• Waterfall model is less flexible to changes, as requirements are finalized early in the process.

• Incremental model allows for change...read more

A program to find unique characters in a word.

• Create an empty array to store unique characters.

• Loop through each character in the word.

• If the character is not already in the array, add it.

• Return the array of unique characters.

Finding the maximum length of palindromic substring from an array of strings using Typescript.

• Iterate through each string in the array

• For each string, iterate through all possible substrings and check if it is a palindrome

• Keep track of the maximum length palindrome found

In Java, heaps are used for dynamic memory allocation. Internal memory allocation in heaps is managed by the JVM.

• Heaps in Java are used for storing objects and dynamically allocated memory.

• Memory allocation in heaps is managed by the Java Virtual Machine (JVM).

• The JVM uses a technique called garbage collection to reclaim memory from objects that are no longer in use.

• Objects in the heap are allocated memory based on their size and type.

• Example: When a new object is created in ...read more

Compose multiple HOCs with render props in a React component

• Create a render prop component that accepts a function as a prop

• Wrap the render prop component with HOCs

• Pass the function as a prop to the HOCs

• Use the function to render the component's content

• Example: withAuth(withTheme(RenderPropComponent))

Object oriented programming is a programming paradigm that uses objects to represent and manipulate data.

• Encapsulation: bundling data and methods that operate on that data within one unit

• Inheritance: creating new classes from existing ones, inheriting their properties and methods

• Polymorphism: ability of objects to take on many forms and behave differently based on context

• Examples: Java, C++, Python, Ruby

Credit card numbers should be stored securely using encryption and hashing algorithms.

• Use encryption and hashing algorithms to store credit card numbers securely

• Never store the full credit card number, only store the last 4 digits for identification purposes

• Use a secure database to store the credit card information

• Implement strict access controls to limit who can access the credit card information

Java is not called the partial OOP concept.

• Java is a fully object-oriented programming language.

• It supports all the principles of OOP such as encapsulation, inheritance, and polymorphism.

• Java allows the creation of classes, objects, and methods to implement OOP concepts.

• It provides features like abstraction and encapsulation to achieve data hiding and modularity.

• Java also supports interfaces, which are a key component of OOP.

• The misconception of Java being a partial OOP conce...read more

Run-time polymorphism is the ability of a method to do different things based on the object it is acting upon.

• Run-time polymorphism is achieved through method overriding in Java.

• It allows a subclass to provide a specific implementation of a method that is already provided by its superclass.

• Example: Animal class has a method 'makeSound'. Dog and Cat classes can override this method to make different sounds.

Closures are functions that have access to variables from their outer scope. Promises are objects used for asynchronous programming in JavaScript.

• Closures are created when a function is defined inside another function and the inner function has access to the outer function's variables.

• Closures allow for data encapsulation and private variables in JavaScript.

• Promises are used to handle asynchronous operations and provide a way to handle success or failure of those operations.

• P...read more