ORACLE Interview Experience | SDE - I

Interview Experience at Oracle

1. Brief Introduction

I started the interview with a quick introduction about myself, my background, and my experience working with Java and data structures and algorithms.

2. Java/OOP Questions

The interviewer asked several Java questions centered around the four pillars of Object-Oriented Programming:

1. Encapsulation
2. Abstraction
3. Inheritance
4. Polymorphism

3. Data Structures & Algorithms (DSA) Questions

1. LeetCode 179: Largest Number
   • Problem: Given a list of non-negative integers, arrange them such that they form the largest number.
   • Link: LeetCode 179 – Largest Number
2. Symmetric Tree Check
   • Problem: Determine if a binary tree is symmetric in structure (ignoring node values).
3. Subset Sum Equal To K
   • Problem: Given a set of integers and a target sum K, determine if any subset of the integers sums to K.
   • Link: Code360 – Subset Sum Equal To K

4. SQL Question

Problem Statement:

Given an Employee table with the following schema:

Write a SQL query that, for a given employee name, returns all managers in the reporting hierarchy.

• Example 1: Input: E1 → Output: E2, E3, E4
• Example 2: Input: E5 → Output: E6

Hint: You may need to use a recursive common table expression (CTE) to traverse the hierarchy.

WITH RECURSIVE ManagerHierarchy AS (
  SELECT Employee, Manager
  FROM EmployeeTable
  WHERE Employee = 'E1'     -- Replace 'E1' with the desired employee
UNION ALL
SELECT e.Employee, e.Manager
FROM EmployeeTable e
INNER JOIN ManagerHierarchy mh
ON e.Employee = mh.Manager
)
SELECT Manager
FROM ManagerHierarchy;

These were the questions I encountered during my Oracle interview. Hope this helps others preparing for similar interviews!