UnitedHealth Software Engineer Interview Questions and Answers

Spring Framework is a powerful, feature-rich framework for building Java applications, emphasizing dependency injection and aspect-oriented programming.

• Spring uses Inversion of Control (IoC) to manage object creation and dependencies, allowing for loose coupling.

• Dependency Injection (DI) can be done via constructor injection, setter injection, or method injection.

• Spring's ApplicationContext is a central interface for p...read more

Generic collections are type-safe and can store any type of data. Non-generic collections can only store objects of type 'object'.

• Generic collections are preferred as they provide compile-time type safety.

• Non-generic collections are slower and can cause runtime errors if the wrong type is added.

• Examples of generic collections include List, Dictionary, and Queue.

• Examples of non-generic collections include ...read more

Triggers are database objects that automatically execute in response to certain events.

• Triggers can be used to enforce business rules or perform complex calculations.

• Types of triggers include DML triggers, DDL triggers, and logon triggers.

• DML triggers fire in response to data manipulation language (DML) events, such as INSERT, UPDATE, or DELETE statements.

• DDL triggers fire in response to data definition language (DDL) ...read more

Managed code is executed by the CLR while unmanaged code is executed by the operating system.

• Managed code is written in languages like C#, VB.NET, etc. and is compiled into Intermediate Language (IL) code.

• Unmanaged code is written in languages like C, C++, etc. and is compiled into machine code.

• Managed code is executed by the Common Language Runtime (CLR) while unmanaged code is executed by the operating system.

• Managed...read more

In, out and ref are parameter modifiers in C# used to pass arguments to a method.

• In parameters are read-only and used to pass values to a method.

• Out parameters are write-only and used to return values from a method.

• Ref parameters are read-write and used to pass values to and from a method.

• In parameters are passed by value, out and ref parameters are passed by reference.

• In parameters are optional, out and ref parameters...read more

Difference between viewdata, viewbag and tempdata

• ViewData is used to pass data from controller to view

• ViewBag is a dynamic object used to pass data from controller to view

• TempData is used to pass data between controller actions or redirects

Ways to improve performance of stored procedures

• Use SET NOCOUNT ON to reduce network traffic

• Avoid using SELECT *

• Use table variables instead of temporary tables

• Avoid using cursors

• Use appropriate indexes

• Avoid using scalar functions

• Minimize the use of triggers

• Use stored procedures instead of ad hoc queries

Stack using queues: push() - enqueue to queue1, pop() - dequeue from queue2 after transferring n-1 elements from queue1 to queue2

• To push an element, enqueue it to queue1

• To pop an element, transfer n-1 elements from queue1 to queue2, dequeue the last element from queue1 and swap the names of queue1 and queue2

• Queue using stacks: enqueue() - push to stack1, dequeue() - pop from stack2 after transferring all elements from ...read more

Doubly linked list is a data structure where each node has a pointer to both previous and next nodes.

• Create a Node class with data, prev and next pointers

• Create a LinkedList class with head and tail pointers

• Implement methods to add, remove and traverse nodes

Yes, I am a leader.

• I have experience leading teams in previous projects.

• I am able to communicate effectively and motivate team members.

• I am proactive in identifying and solving problems.

• I am able to delegate tasks and trust team members to complete them.

• I am constantly seeking to improve my leadership skills through learning and feedback.

A program to generate the Fibonacci series up to n terms provided by the user.

• Fibonacci series starts with 0 and 1.

• Each subsequent number is the sum of the previous two.

• Example: For n=5, the series is 0, 1, 1, 2, 3.

A program to find factorial using recursion.

• Define a function that takes an integer as input.

• Check if the input is 0 or 1, return 1 in that case.

• Otherwise, call the function recursively with input-1 and multiply it with the input.

Indexes are data structures that improve the speed of data retrieval operations in a database. Views are virtual tables created from queries.

• Indexes are used to quickly locate data in a database by creating a sorted structure that allows for efficient searching.

• Views are virtual tables that are created by executing a query and storing the result set as a named object.

• Indexes can be created on one or more columns of a t...read more

Designing employee and department tables with primary and foreign keys for relational database management.

• Employee Table Fields: EmployeeID (PK), FirstName, LastName, Email, Phone, DeptID (FK)

• Dept Table Fields: DeptID (PK), DeptName, Location

• Primary Key (PK) in Employee Table: EmployeeID uniquely identifies each employee.

• Primary Key (PK) in Dept Table: DeptID uniquely identifies each department.

• Foreign Key (FK) in Empl...read more

Indexes are implemented using B Trees and B+ Trees.

• B Trees and B+ Trees are data structures used to organize and efficiently search data in databases.

• B Trees are balanced search trees that store data in nodes with multiple children.

• B+ Trees are similar to B Trees but have additional features like leaf nodes that form a linked list.

• Indexes are created on specific columns of a database table to improve query performance.

• ...read more

Other than indexes and tables, a DBMS also includes views, stored procedures, triggers, and functions.

• Views: Virtual tables that are based on the result of a query. They provide a way to simplify complex queries and restrict access to data.

• Stored Procedures: Precompiled sets of SQL statements that can be executed with a single command. They enhance performance and allow for code reusability.

• Triggers: Special types of s...read more

A database administrator manages and maintains databases, ensuring their security, performance, and availability.

• Designing and implementing database structures

• Installing and configuring database software

• Monitoring and optimizing database performance

• Ensuring data integrity and security

• Backing up and restoring databases

• Troubleshooting and resolving database issues

• Collaborating with developers and system administrators

• Pla...read more

Inorder traversal of a binary tree visits nodes in left-root-right order, yielding a sorted sequence for BSTs.

• Inorder traversal visits the left subtree, then the root, and finally the right subtree.

• For a binary tree: Given nodes A, B, C, where A is the root, B is left child, and C is right child, the order is B, A, C.

• Example: For a BST with values 2, 1, 3, the inorder traversal results in [1, 2, 3].

• Recursive implementa...read more

This task involves sorting numbers and using binary search to find a specific number in the sorted array.

• 1. Sort the array: Example - [5, 2, 9, 1] becomes [1, 2, 5, 9].

• 2. Implement binary search: Start with the middle element and compare it to the target.

• 3. If the middle element is equal to the target, return its index.

• 4. If the target is less than the middle element, search the left half.

• 5. If the target is greater, s...read more

Types of integrity in DBMS include foreign, referential, and domain.

• Foreign integrity ensures that foreign key values in a table match primary key values in another table.

• Referential integrity ensures that relationships between tables are maintained, preventing orphaned or invalid data.

• Domain integrity ensures that data in a column adheres to specified data types, formats, or constraints.

• For example, in a database for ...read more

Agile methodology is an iterative and incremental approach to software development.

• Agile methodology emphasizes collaboration, flexibility, and customer satisfaction.

• It involves breaking down the project into small, manageable tasks called user stories.

• Teams work in short iterations called sprints, typically 1-4 weeks long.

• Regular meetings like daily stand-ups and sprint reviews are held to track progress and gather fe...read more

In 3-5 years, I see myself as a senior software engineer leading a team of developers on innovative projects.

• Advancing to a senior software engineer role

• Leading a team of developers on projects

• Working on innovative and challenging projects

• Continuing to learn and grow in the field

I am a passionate software engineer with experience in developing web applications using various technologies.

• Experienced in full-stack web development

• Proficient in languages such as JavaScript, Python, and Java

• Familiar with frameworks like React, Node.js, and Django

• Strong problem-solving skills and ability to work in a team

• Completed projects like e-commerce website using MERN stack

I want to learn how to play the piano.

• I have always been fascinated by music and the piano in particular.

• Learning to play an instrument can be a great way to relax and unwind.

• Playing the piano can also improve cognitive skills and memory.

• I believe learning to play the piano will bring me joy and fulfillment.

My strengths include problem-solving skills and attention to detail. My weaknesses include public speaking and time management.

• Strengths: problem-solving skills, attention to detail

• Weaknesses: public speaking, time management

Activity flow diagrams for Ola cabs management system and washing machine.

• Ola cabs management system: User books a cab -> Driver accepts the ride -> User gets picked up -> User reaches destination -> Payment is made.

• Washing machine: User selects wash cycle -> Machine fills with water -> Detergent is added -> Machine agitates clothes -> Water drains -> Clothes are rinsed -> Machine spins clothes -> Cycle ends.