Received an email from a job portal regarding the interview. The email mentioned that the interview would be conducted in three technical rounds. In the first and second rounds, candidates were asked to write basic programs and queries on paper. After the second round, everyone was told they could leave, and details about further rounds would be communicated within 2-3 days. I haven't heard anything from Oracle since then.

Write a Java program that demonstrates the following OOP features:

• Encapsulation
• Inheritance
• Polymorphism

Write a program to find a number in an n*n matrix with minimal iterations. After the initial program was written, the request was to reduce the number of loops.

Write a function for calculating the Least Common Multiple (LCM).

Write a program using JDBC to fetch employee details from a table if it's their birthday. (Consider the leap year birthday case.)

Create an ER diagram for student and faculty tables with a many-to-many (m2m) mapping. Following this, answer 5-6 queries on the schema, including joins, GROUP BY, HAVING, and subqueries.