Table of Content

• About Oracle
• Characteristics of Oracle
• Oracle Selection Process
• How to answer Oracle interview questions
• Oracle interview questions
• Conclusion
• FAQ

About Oracle 

Oracle is one of the best software multinational company, that provides cloud services, database management systems and other enterprise software products. The headquarters of Oracle is in Redwood City, California. It was founded in 1977, by Larry Ellison, Bob Miner, and Ed Oates.

Mainly companies working on building tools for database management system and software development like enterprise resource planning (ERP) software, customer relationship management (CRM) system, supply chain management (SCM) etc.

Characteristics of Oracle 

Because of focusing on innovation and customer satisfaction the company regularly recruits the talented candidates that are involved in software development. Company hires the best software engineers around the world.

The company focuses on research and developing innovative products as per customer’s satisfaction. Companies make significant investments in R&D. Its particular qualities and ways of operation have allowed it to maintain its position as a leader in the technology sector and to keep generating growth and value for its clients and stakeholders.

Oracle Selection Process 

The interview process is of three to four rounds, technical and aptitude test, technical round 1, technical round 2 and HR round. We are discussing each round in a brief. 

• Technical Aptitude questions round: In this round, there are multiple choice questions related to software engineering and aptitude questions. There may be the possibility of English grammar questions. You need at least 80% in this round. Jasmin scored 82% and was selected for the next round.
• Technical round 1: In this round, there are three problems, out of three you must solve at least two problems in a given time of 1 hr, time may vary. The questions may be on data structure or algorithms in software engineering.
• Technical round 2: This is a technical interview round, in this round the technical lead tests the technical knowledge about software engineering. Ask the questions related to data structure, algorithms, product development methodology and database management.
• HR round: In this round your communication skills will be tested. HR asking the most common questions like salary expectation, checking your strength, weakness, IQ questions, problem solving techniques etc.

How to answer Oracle interview questions 

Oracle is one of the best cloud service providing services, therefore you must prepare for the interview very well. There are some tips to bit the interview of Oracle:

• Research about company for the position: Research about company history, products developed by company, history, mission.
• Coding practice: Oracle is a data processing company, therefore you must practice the basic coding problems of languages like Java, C, C++.
• Read Job description: Read the job description carefully, and prepare yourself.
• Prepare for behavioural questions: Oracle often gives a situation and asks how you can handle the situation.
• Be Prepare for technical questions: Search for all possible questions of required languages. Clear the basic concepts. 

By following these tips, you can increase your possibilities of performing great in the meeting and finding the occupation at Oracle.

Oracle Interview Questions 

Oracle Technical Interview Questions 

1. Explain 4 pillars of object-oriented programming concepts.

The four main concepts of object-oriented programming (OOP) are as follows:

Encapsulation: Encapsulation is the process of wrapping data and code into a single unit. It helps to keep code organized.

Inheritance: Inheritance is a mechanism that allows one class to inherit properties and behaviours from another class. Inheritance promotes code reuse and reduces code duplication.

Polymorphism: Poly means many and morphism means forms. Polymorphism is used to create many forms of an object. In OOP,  we can achieve polymorphism through method overloading and method overriding. 

Abstraction: Abstraction is the process of hiding the implementation of an object from users and it's used when we hide the complicated details of something and show only the most important parts to people. We do this by using special types of classes and rules called abstract classes and interfaces.

2. Distinguish between an interface and an abstract class?

Abstract class: It contains both abstract and non-abstract methods. It supports multiple inheritance. Use abstract keyword to declare abstract class. The keyword extend is used to abstract the class. 

Inheritance: Inheritance contains only abstract methods. It does not support multiple inheritance. Use interface keyword to declare interface class.

3. How will you find the address of a variable without using a pointer? 

We can use address of operator (&) as follows:

#include <studio.h>

int main ()

{

    int a;

    int b;

    printf(“Address of a: \n”, &a); 

    printf(“Address of b: \n”, &b);

                return 0;

}

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4. Explain the difference between a primary key and a foreign key?

Primary key is unique for each row. It is used to identify each row. Foreign key is the primary key of another table.

5. What is a cluster in the database?

A cluster in Oracle refers to a specific type of data organization or indexing technique used to physically store related data together on disk. 

6. Can you explain the concept of data integrity in the databases?

Data integrity leads to accuracy, completeness and consistency of the database. Using primary key, foreign key leads to data integrity in the database.

7. How do you troubleshoot performance issues in an Oracle database?

To troubleshoot performance issues in an Oracle database, you can:

• Use Oracle's Automatic Workload Repository (AWR) to gather and analyze performance data.
• Use Oracle's Enterprise Manager to monitor performance and diagnose problems.
• Use Oracle's SQL Tuning Advisor to analyze and tune SQL statements.
• Use Oracle's Explain Plan feature to analyze the execution plan of SQL statements.

8. Can you explain the different types of indexes available in Oracle databases?

Oracle database supports the different types of indexes:

• B-tree index: the default index type used for most situations
• Bitmap index: suitable for low-cardinality columns
• Function-based index: created based on a function or expression
• Reverse key index: reverses the bytes of the index key value
• Domain index: used for text search and retrieval.

9. What are some of the common SQL functions used in Oracle database?

Some common SQL functions in Oracle include:

• Aggregate functions are as: SUM, AVG, COUNT, MIN, and MAX
• Date and time functions: SYSDATE, TO_DATE, and ADD_MONTHS
• String functions: CONCAT, SUBSTR, and TRIM
• Mathematical functions:  ABS, CEIL, FLOOR, and ROUND.

10. What are the different objects of the database?

Table, views, sequence, indexes, databases triggers are the objects of database

11. What is a tablespace?

In a database management system (DBMS), a tablespace is a logical storage unit for organising and storing data.A tablespace is generated within a database in relational database systems and connected to one or more data files that are kept on the underlying storage system.

12. What is BLOB datatype?

For handling huge binary data, such as pictures, music files, video files, and other multimedia objects, databases utilize the BLOB (Binary huge Object) datatype. It is intended to store and retrieve binary versions of unstructured data.

13. What are different types of joins in the oracle database?

The JOIN operations are:

• INNER JOIN: This is an explicit join clause between two tables.
• LEFT OUTER JOIN: This is an explicit join clause between two tables, and used to identify unmatched rows from the first table.
• RIGHT OUTER JOIN:  This is an explicit join clause between two tables, and used to identify unmatched rows from the second table.
• CROSS JOIN: It specifies a join that produces the Cartesian product of two tables. It has no explicit join clause.
• NATURAL JOIN: Specifies an inner or outer join between two tables. It has no explicit join clause.

14. What is an integrity constraint?

An integrity constraint is a declaration defined as a business rule for a table column. To ensure accuracy and consistency of data in a database we can use  integrity constraints. The types of integrity constraints are domain integrity, referential integrity.

15. What are the various constraints used in Oracle?

Following are constraints used:

• NULL – When the value of particular column is not compulsory, we can NULL values
• NOT NULL – It is used if a particular column cannot be NULL, it contains some value.
• CHECK – It is used to compare values in the given column to meet the specific criteria
• DEFAULT – It is used to the value is default value

16. Explain Cartesian join and cross join?

There are no differences between the join. Cartesian and Cross joins are the same. Cross join gives the cartesian product of two tables – Rows from the first table are multiplied with another table which is called cartesian product. Cross join without where clause gives Cartesian product.

17. What is the fastest way to fetch data from a table?

We can fetch the data by row ID, it is the easiest and fastest way of fetching data.

18. What is PL/SQL?

PL/SQL is an extension of SQL in Oracle.Procedural Language/Structured Query Language is known as PL/SQL. The Oracle Corporation created a programming language for the express purpose of managing Oracle databases. 

19. Explain Software Development life cycle?

The Software Development Life Cycle (SDLC) has six phases that must be followed to produce and deliver high-quality software. Phases are as following:

• Requirements Gathering: The developer identifies, collects, and defines issues and requirements, and customer expectations related to the software application. Generating software specifications, creating documentation, issue tracking, and product planning, allocating the resources, are some tasks done during this phase.
• Software Design: In this phase, the team makes decisions regarding structure and architecture and makes software solutions. 
• Software Development: In this phase actual development starts based on the design decisions made during earlier stages of the project
• Testing and Integration: After software is done, we need to ensure quality of it. Quality assurance is a part of testing.
• Deployment: after testing it the next stage is to install the software.
• Operation and Maintenance: After software is installed, we need to maintain it. 

20. State different types of SDLC model?

The different types of SDLC model:

• Waterfall model
• Spiral model
• Incremental model
• Agile Model
• Big bang model
• Iterative model

21. Explain the concept of modularization? 

Modularization is a design strategy that includes breaking down a system into smaller, independent modules or components.

22. What is a data flow diagram?

A Data Flow Diagram (DFD) shows the flow of a data process of a system. The DFD diagram contains inputs, outputs, and paths between each stage. We can use different  shapes like rectangles, circles, and arrows, as well as short text labels.

23. What are software requirements?

Software requirements are a functional description of a software system which is to be designed. It is assumed to be the description of the system, its functionalities, and features.

24. What is quality assurance and quality control?

Quality Assurance checks if proper process is followed while developing the software and Quality Control checks the quality of software product in the maintenance.

25. What is debugging in the software development process?

Debugging is the process that removes errors after completing the software. It is a very important part of the testing process for successful installation.

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Oracle HR Interview Questions

1. Tell me about yourself?

I have five years of experience as a software engineer and a bachelor's degree in computer science. I'm a specialist in building mobile and internet apps, and I speak Java, Python, and JavaScript with ease.

2. Why did the company hire you?

I firmly feel that my strong programming abilities, capacity for teamwork, and background creating sophisticated software programmes make me an excellent choice for this position.In order to provide high-quality software on time, I've worked on a variety of projects that needed collaboration with other programmers and stakeholders.  

3. What do you know about the company?

I've done some research on the company, and am impressed by how dedicated it is to providing its customers cutting-edge software solutions. I know the business is well known in the sector for producing high-quality software on schedule and under budget. I am also aware that the business places a high priority on staff development and offers chances for development and progress.

4. What would be your idea that contributes to company progress?

One concept I have is to create new software that aids businesses in automating their HR procedures, such as hiring new employees, performance management, and benefits administration. Companies might concentrate on their main business activities as a result of the time and money they would save. This, in my opinion, would support the company's objective to deliver cutting-edge software solutions and would further its development and expansion.

5. How long would you work for us if hired?

When asked this question, stating that you are seeking a long-term career opportunity and that you are devoted to honing your talents and making a positive impact on the organisation. As fresh prospects inside the organisation present themselves, you might also say that you are interested in finding out more.

6. Why do you want to work for Oracle?

What precisely attracts you to Oracle as a company should be the main emphasis of your response to this question. Discuss how the company's culture, mission, and values connect with your own professional objectives and personal principles. Additionally, you are welcome to bring up any initiatives, services, or products in particular that Oracle is working on and that you are interested in. Another sensible option is to explain how your credentials and history make you a good fit for the company and how you can contribute to their success.

Conclusion 

In this article, we see the Oracle interview process, what Oracle actually, technical interview, HR interview questions. There is a possibility of three to four rounds, first is technical aptitude questions, technical coding interview 1, technical interview 2 and last is HR interview. The interviewer asks technical interview questions on software engineering, database management, core java, python, C, C++, etc programming languages. You must prepare for all possible interview questions. 

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