I've been part of the LC community for more than 3 years now and hence I want to contribute back to the community by sharing my experience.

The following interview is an On-campus selection that happened in my college.

Compensation details, etc shall be posted later in a seperate post.

Status: Fresher (Graduating in 2023) | Tier 2 College in India
Experience: 2 month internship at a FinTech startup
Date: July 2022

The interview process by Oracle for a fresher is generally as follows:

• Aptitude
• Online Coding Round (Optional)
• Three rounds of technical interviews

The second round i.e. coding round is generally based on luck i guess. Since this was on-campus, I think they skipped that part.

Round 1 : Aptitude (2 hours)
This round consisted of multiple questions ranging from logical reasoning, statistics, data analysis to CS Fundamentals and English. Some CS Fundamentals that I couldn't answer and could only guess were based on AVL and Red Black Trees.

This aptitude test was conducted on their platform called proaptitude. Each section had its own set of subsections and each such subsection had its own alloted time within which you were required to finish that subsection.
Example: English had sections like Reading, Writing, etc, where Reading had a slotted time of 4 minutes and Writing as 6 minutes.

After the aptitude, the selected candidates were invited to interview rounds.
All the three rounds of interview happened on the same day

Round 2: Technical Interview 1 (30-40 minutes)

I started by greeting the interviewer and then the basic introductions happened.

The round started off with a DSA question. It was very similar to subarray maximum sum(https://leetcode.com/problems/maximum-subarray/)

Once this was done, some questions related to Computer Networks and Operating Systems were asked. It involved questions around Semaphores, Multithreading and Multiprocessing. As I had experience in Python, the interviewer proceeded to also ask me about Global Interpreter Lock, Deep Copy and Shallow Copy in Python.

Then he went ahead to ask me another DSA question. It was similar to finding the diameter of a binary tree (https://leetcode.com/problems/diameter-of-binary-tree/)

Once this was done, he was satisfied with how I approached the problems.

Round 3: Technical Interview 2 (30-40 minutes)

This round started of with some introduction. The interviewer asked me my experience in C++. I knew that if I would lie, I was going to be easily grilled as he seemed pretty experienced. Hence I stood my ground and stated that my experience lies with Java, C and Python majorly.

He stated that he doesn't know much about Java(which I didn't expect). Then he proceeded to ask some questions from C which ranged from how memory is handled(Stacks and Heaps), structs vs union, etc.

Then he shifted to Computer Networks and Operating Systems where he questioned me about Piggybacking, TCP UDP examples, IPC and how pipes function.

He later shifted the talk to asking about my academics and asked whether I had projects built using C. He then proceeded to ask me about sockets, SIGABRT signal, etc.

At the end, he also asked me to tell a SQL query that shall return the second larget salary from an employee table.

Overall, this round didn't go that great as I fumbled a bit in fundamentals of C.

Round 4: Technical Interview 3 (30-40 minutes)

This round was the highlight of my day as the interviewer was super friendly and was always interactive when I gave some answer or tried answering. This round didn't involve much of CS Fundamentals or DSA, rather it involved scenario based questioning where the interviewer expected me to think and answer thereby he could understand my thinking abilities.

This round started off with a basic quick introduction and the interviewer proceeded to ask a standard HR question, "Tell a time where you improved performance of your project or anything that you were working on". I told him a situation that occured in my internship and how I tackled it, he felt satisfied with my answer.

He then proceeded to ask me if I had any hands-on experience with any cloud service like AWS, GCP, etc.

Then he presented me a scenario. First he explained what Big Data is, and gave a situation where there would be a lot of data that needs to be processed. He told me to think about it and come up with what I would use and why. He clearly stated that he isn't expecting the right answer, he just wants to know my thoughts and what I know about such scenarios.
The above situation was something I knew about clearly and hence I spoke about using Hadoop clusters, and if the data was in real time, we could jump into using Spark as well.

He was satisfied with my answer and went ahead to ask about MATLAB and Image Processing as they were present in my resume.

He later asked me about my experience with Java Spring and asked me to give him a scenario where microservices would be beneficial.

Then, he presented me with another scenario where he asked me to improve the read and write performance of a DB. I started by stating and explaining indexing and sharding as that was something that popped up in my head immediately. Later, he stated to also focus on write improvements, this hinted me to also mention caching. He later went on to explain why caching would be beneficial in this scenario.

This was the end of the interviews and I was told that the results would be announced by midnight.

Result: They offered me an Internship + Full Time role.

Suggestions

• The key takeout from the complete interview process is to be ready for any kind of question. I never expected them to ask something on Cloud, I was expecting questions involving OOPS and Design Principles instead.
• Another important point if you are a beginner is to always talk while you are solving a DSA question. Do not jump into the optimum solution directly, talk about the brute force solution and then talk about the optimum solution.
• OOPS, Operating Systems, Computer Networks, DBMS are important as any topic from them can be asked, so prepare well for all these subjects.
• The DSA questions are generally in the medium scale so if you solve questions frequently asked by Oracle, you shall be in an advantage.
• Have confidence in yourself and think out loud, that is all that matters.