Oracle Interview Experience (Server Technology) | On-Campus 2020 (Virtual)
Oracle came to our campus for a server technology profile. Round 1 was an online test, audio and video proctored. The whole interview process was on zoom meetings. It was a very smooth virtual experience; there were counter rooms inside zoom meetings for post and pre-interview sessions.
Round 1 was an online test consisting of four sections. Every section had a different time limit. One has to be quick and efficient to solve all the questions. The overall difficulty was medium.
1. Aptitude – Basic Arithmetic Aptitude, Logical Reasoning, Data Interpretation, Patterns.
2. Language – Comprehension, Sentence reordering, Grammatical error, Synonyms & Antonyms.
3. Coding MCQ – Code snippet, identify the output or error, time complexity. (most of them was on trees, graph, and searching techniques)
4. Computer Science Subjects – DBMS, Data Structures, OS, OOD
Out of 127 students, 46 students shortlisted for technical interview rounds.
Round 2 – technical interview round 1
The interviewer started with the basic introduction. Then he had a glance over the resume, as I have mentioned data structure as one of my skills, so he started with questions on Data Structures.
– What is a Binary Search Tree, Explain?
– What is Balanced Tree, Skewed Tree, and Complete Tree?
– How to insert, delete, and search an element in a binary search tree and explain each operation’s average and worst time complexity?
– How to insert an element in the array (assume the number of elements is less than the array’s fixed size) also state the time complexity?
– What is Polymorphism, runtime, and compile-time Polymorphism, explain with an example?
– What is a virtual function, explain working and implementation, and why they are used (he went deeper into function overriding )
– What is recursion, write code for Fibonacci both recursively and iteratively?
– Why recursion is used over the iterative approach? What if the base condition or termination condition is wrong, which type of error gets generated (long discussion on how recursion internally uses Stack), memory.
– Can you calculate the size of the memory using recursion?
– Give an elementary example to create an infinite loop. (Ans. while True: )
– Explain and code on the notepad to detect a loop in a linked list.
– What are the vectors in C++? Have you heard STL in C++?
– What is malloc(), calloc(), and free() functions, write syntax, and explain how they work?
– Puzzle: What is the angle between the minute hand and an hour hand when the time is 10:20 AM.
Round 3 – Technical interview round 2
This round was a coding round on a shared coderpad. Before solving, she asked what lockdown did bring change and what skills I worked on during lockdown.
1. There are N balls in a bag, and every ball has a number on it. Print the number where the sum of similar balls is equal to target = 20. (use any language of choice)
For e.g. input: [5,20,5,11,8,5,5,3,1]
(Talk and ask how input and output would be like, explain what you understood before start coding)
2. Give a real-life example of Stack.
3. Implement Queue from scratch such that can be imported or use in the different programs.
4. Explain Principles of Object-Oriented Programming.
Round 4 – Technical interview round 3
1. What are the pointers? Code with an example. Explain the working of a pointer.
2. Why Pointers are used and state the Importance.
3. Are pointers used in Python, is there any similar functionality in Python to call functions as pass by value, reference, or address.
4. What is the Pointer of a pointer? Implement.
5. How the use of pointers can be problematic or create difficulty
We had an in-depth discussion on pointers on it’s working and implementation.
6. What is Function overriding? Explain.
7. How C, C++, and Python are different?
8. What is object-oriented programming, and how is it different from the structured programming language?
9. What is inheritance, and how is it implemented? State Example.
10. What is Normalization? Why do we normalize a database, give examples, and explain with every Normal form?
11. Explain in-depth one of the best projects (according to me) mentioned on the resume. Then he cross-questioned me on that.
12. Any questions that I would like to ask? ( I asked him about autonomous databases )
The HR was directing and coordinating us after and before every session.
Every round was an elimination round. There was a total of three technical rounds. Started sharp at 10:00 AM till 4:00 PM
Explain every concept with a good example, cover base cases. Be confident and vocal throughout your approach towards the problem. Be prepared to code down the example.