40+ Oracle Technical Interview Questions

Oracle is a multinational technology corporation that offers database management solutions, enterprise products, and cloud solutions. It was the second-largest software enterprise in 2020 in terms of market capitalization and revenue, making it a highly desirable company for developers and software engineers. The Oracle technical interview process is largely similar to processes at FAANG and other tier-1 companies. The interview rounds test your core coding and programming skills, besides evaluating your psychological and behavioral traits.

Oracle has an inclusive cultural environment that makes it one of the top places to work for engineers. Its decentralized culture, owing to the acquisition of several smaller companies, ensures the elimination of any unwelcome interference in the day-to-day operation of teams across the board.

Expert’s Quotes:

"When you innovate, you've got to be prepared for everyone telling you you're nuts."

–Lawrence Joseph Ellison

(co-founder and former CEO of Oracle Corporation)

In this article, we’ll look at some common interview questions asked at Oracle’s technical interview. We’ll also cover some tips to help you get past the various interview rounds and land an offer.

Here’s what we’ll cover:

• What does Oracle look for in software engineers?
• Oracle’s technical interview process
• Oracle interview questions
• Tips to crack Oracle’s technical interview
• Get interview-ready for your next big interview
• FAQs about Oracle Technical Interview Questions

What Does Oracle Look for in Software Engineers?

Oracle essentially looks for polished problem-solvers with the ability to tackle modern-day problems through sound analytical skills. Problem-solving is a key skill that Oracle recruiters look for in tech interviews. So building your skills through diligent effort and persistent practice is extremely important to succeed in tech interviews at Oracle.

In a nutshell, here’s what Oracle looks for in software engineers or coding engineers who apply for engineering and developer roles:

You can solve tricky and complex problems: The coding interview requires you to solve tricky problems around core data structures and algorithms. Your ability to brute-force solutions and approach solutions from multiple angles to find the most optimal one is closely evaluated.

You exhibit the right attitude and demeanor: Behavioral interviews are an extremely important part of the technical interview process at big tech companies. It’s no different at Oracle, where your ability to adapt and your conduct in workplace-related situations is assessed. Hiring managers essentially look for candidates who display the right behavioral attitude and fit into the company’s culture.

Your distributed systems design concepts are strong: Your knowledge of distributed systems is extensively evaluated at Oracle’s on-site interview. Becoming thorough with systems design concepts is crucial if you crack the on-site interview at Oracle.

Oracle Technical Interview Process

As mentioned earlier, the technical interview process at Oracle is largely similar to that at other tier-1 companies. Here’s what you can expect when you get shortlisted for Oracle’s technical interview:

The Initial Phone Screen: During the phone screen round, your skills and experience are assessed to see if you’re the right fit for the role. This is the initial interview round that takes place with a recruiter from human resources. Updating your LinkedIn profile with the right keywords is key to getting contacted for the initial phone screen.

The Technical Phone Screen: This is where your approach to problem-solving is evaluated before you’re invited to the on-site interview rounds. You can expect 1-2 coding problems of moderate difficulty. Your ability to brute-force the solution and write bug-free code to solve the problem is tested. You can also expect a few questions about your core technical skills and past employment experience.

The On-site Interview: On-site is where problem-solving skills are further tested. The on-site typically comprises a coding round, design round, and behavioral round. Senior developer positions are more focused on the design round, while junior positions focus more on the coding round. Behavioral rounds are important for all positions and typically carry more weight for senior developer and managerial positions.

Oracle Interview Questions

The interview questions asked at Oracle’s tech interview can be classified into coding questions, design questions, and behavioral questions. Let’s look at some sample questions for each category.

Oracle Coding Interview Questions

Before getting into the questions, the following are the topics you should prepare for the coding interview. These topics feature in both the technical phone screen and the coding round in the on-site interview.

• Arrays, strings, and linked lists
• Sorting algorithms — quicksort, merge sort, heap sort, etc.
• Hash tables and queues
• Recursion
• Trees and graphs
• Graph algorithms, including greedy algorithms
• Dynamic programming

Here are some coding questions that are asked at Oracle’s coding interview:

1. Write a program to implement a Queue using two stacks. (Click here for the solution)
2. You’re given two Linked Lists, “A” and “B,” that are sorted. Write a code to merge the two Linked Lists. (Click here for the solution — K sorted Lists)
3. For a given unsorted array comprising non-negative integers, write a function to find the contiguous subarray that returns the sum of non-negative integers in the array.
4. You’re given two arrays that are sorted and of varying sizes. Write a code to merge the two arrays such that elements in the merged array appear in increasing order.
5. For a given Linked List “L,” write a function to pick a random node from the Linked List.
6. For a given array of n positive integers, write a function to determine the inversion count of the array.
7. For a given Binary Tree T, write a function to print the right view of the tree.
8. You’re given a Binary Tree T. Write a code to print the height of the Binary Tree.
9. For a given Binary Tree, write a function to connect the nodes of the Binary Tree that are at the same level.
10. You’re given a binary search tree with unique values; two node values are given. Write a function to find the lowest common ancestors of the two nodes.
11. You’re given a Binary Tree. Write a code to convert it to a Doubly Linked List (DLL) In-Place. The left and right pointers in the nodes are to be used as previous and next pointers, respectively, in the converted DLL.
12. Write a code to count the leaves in a given Binary Search Tree BT.
13. Write a code to implement the Serialize and Deserialize functions on a given binary search tree.
14. Given an array of integers, write a program to return the next greater element for each element in the array. The array comprises all distinct numbers. If a greater element to the right of a given element doesn't exist, the value returned in that position should be -1.
15. For a given set of 2 sorted arrays, “X” and “Y” with respective sizes “n” and “m,” write a code to merge the two sorted arrays such that their characters appear in decreasing order.
16. For a given set of 2 arrays “X” and “Y” consisting of positive integers, write a code to find the total no. of pairs to satisfy the condition x^y>y^x, where “x” is an element of array “X” and “y” is an element of array “Y.”
17. For a given array, “K,” where all the elements in the array are distinct, write a function to find the Kth smallest element where “K” is a number and is smaller than the array’s size.
18. You’re given an array “X” of size “N,” containing sets of 0s, 1s, and 2s. Write a program to sort the array elements in ascending order.
19. For a given array “X” of N positive integers, write a function to return the value “True” if a particular triplet (a,b,c) accurately satisfies the condition: a^2+b^2=c^2 (this is commonly called the Pythagorean Triplet problem).
20. Write a program to find the square root of a given integer “K.”

Tips for Coding Interview at Oracle

• Oracle focuses more on questions around graphs and trees. So make sure you’re through with Binary Trees, Binary Search Trees, and Greedy Algorithms.
• Dynamic programming is another important area that you must cover extensively, as you can expect questions around the concept.
• Arrays and strings are also important topics to cover. A good number of questions feature from these topics.
• Practice whiteboard coding, especially for the on-site interview. Your ability to write bug-free code is closely evaluated.
• Always approach problems based on patterns you’ve worked with in the past. This way, you can solve more tricky and complex problems and find optimal solutions to them.
• Pay close attention to the time and space complexity of problems asked at the interview.

For more problems and solutions, visit the Problems page.

Oracle Systems Design Interview Questions

Systems design is an important concept for the Oracle on-site. Here are the topics you should look to cover for your design interview:

• Basics of systems design
• Basics of networking
• Scaling distributed applications
• Replication
• Sharding techniques
• Measuring the performance of scalable systems
• Cache
• Storage and retrieval
• MapReduce and distributed file systems
• Systems design case studies
• Basics of API design

Below are the type of design questions you can expect at Oracle’s on-site interview:

1. Design a parking garage with a ticketing system that notifies users about available parking spaces and issues tickets.
2. Design a chatbot service that sends notifications, takes customer requests, and replies to customer queries.
3. Design a fool-proof video streaming service where consumers can stream and search for videos they want to watch.
4. Design an online bookstore where consumers can purchase books by making online payments and also view the list of all available books.
5. Design an API Rate Limiter.
6. Design a Messaging service that connects users.
7. Design a traffic control system that accurately directs traffic without the probability of accidents.
8. Design a proximity server that works as a gateway between users and the internet.
9. Design a web crawler that optimally crawls the right web pages based on user searches.
10. How would you design an e-commerce website that accepts user payments through different modes (credit card/debit card, etc.)?

Recommended Reading:
Google Systems Design Interview Questions for Software Developers
Amazon System Design Interview Questions

Tips for System Design Interview at Oracle

• Spend at least 2-3 weeks focusing only on the design part. Oracle, being a database management company, gives considerable weightage to design interviews.
• Develop the ability to design complex, scalable systems with low latency.
• Discuss your design approach with the hiring manager during your interview to give them a window into your thoughts.
• Refer to good resources to guide you through your prep journey. Interview Kickstart’s Technical Masterclass is specifically designed to help you nail tough technical interviews at the biggest companies.
• Practice mock interviews to know where you stand and overcome your shortcomings. Interview Kickstart offers mock interviews with actual tech leads and hiring managers from FAANG. Sign up for our FREE webinar to learn more.  

Oracle Behavioral Interview Questions

Behavioral interviews are highly influential in hiring decisions. The purpose of behavioral interviews is to assess if you’re the right cultural fit. Here are some sample behavioral questions asked at Oracle’s on-site interview:

1. What is your biggest learning from the most difficult project you’ve worked on in the past?
2. Have you missed project deadlines in the past? What was the reason, and how did you go about completing it at the earliest?
3. Have you ever been stressed due to a strenuous project? How did you deal with it?
4. How do you maintain a healthy work-life balance and high productivity levels?
5. Have you worked on multiple projects simultaneously? How did you prioritize and plan your schedule?
6. Tell us about a time when you had to make an important decision with little available data.
7. Tell us about a time when a colleague was uncooperative. How did you handle the situation?
8. Have you been in the middle of a workplace conflict in the past? How did it go down, and how did you deal with it?
9. Have you disagreed with a superior/manager? What was the disagreement about, and how was it resolved?
10. Tell us about a time when you had to adapt differently to take on a new project.
11. Tell us about a time when you had to share crucial learnings from a project with your team members and how it helped them.
12. Tell us about a time when you faced a difficult client. How did it turn out?

Tips for Behavioral Interview at Oracle

• Practice mock interviews: Mocks are a brilliant way to know where you stand and what areas you should focus more on improving.  Practicing mock interviews with hiring managers and technical leads from FAANG companies will certainly put you ahead of the race.

Mock interviews work! Don’t just take our word for it — check out these testimonials from Interview Kickstart alums who landed jobs at Oracle: Rajat Roy | Rohith Nedunuri

• Prepare answers to questions: Prepare answers to behavioral questions commonly featured in tech interviews, using the STAR method (Situation, Task, Action, and Result). This way, interviewers will have a complete context of what was at stake and what actions they took.
• Ask the right questions: Asking the right questions is also equally important to make the right impression in behavioral interviews. Ideally, you should be asking questions about the company’s culture and day-to-day responsibilities around your role.

Recommended Reading:
Amazon Behavioral Interview Questions
Facebook Behavioral Interview Questions
9 Important Tips to Nail Coding Interviews in 2021

FAQs About Oracle Technical Interview Questions

1. Are Oracle interviews hard?

The types of questions asked in a typical Oracle interview are often of moderate level, which fluctuates from person to person. Because the number of interview rounds varies from four to seven, it can be scary for a candidate at times. But if you're committed, it will be worthwhile. The quality of interview preparation determines whether the procedure appears easy or difficult. Glassdoor users rated their Oracle interview experience as 70.8% good, with a difficulty score of 3.10 out of 5.

2. What is the salary of a technical lead in Oracle?

The annual base pay of a Technical Leader at Oracle in the United States is approximately $159,054. This salary is 51% above the national average salary in the US. (Source: Indeed.com)

3. How long is the Oracle interview process?

There are two stages to the interview procedure. There is a virtual assessment first, followed by a phone conversation from HR to verify whether you're interested in the post, which usually lasts about 10 minutes. Finally, the hiring manager will conduct a technical interview with you.

4. What not to do in a technical interview?

Refrain from speaking over the interviewer, forgetting to express your thought process, memorizing solutions without grasping them, dismissing feedback, ignoring the value of soft skills, and forgetting to ask questions about the organization and role during a technical interview.

5. What is the difference between a functional interview and a technical interview?

A functional interview determines how well an applicant's abilities match the particular demands of a post, with emphasis on their capacity to accomplish tasks and bring value to the team. A technical interview, on the other hand, assesses an applicant's skills in technical abilities and problem-solving, sometimes through coding tasks or technical issues.

Get Interview-ready for Your Next Big Interview

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