In a database, you have entities (which have attributes), and relationships between those entities. Managing them is key to preventing chaos from engulfing your database, which is where the concept of keys comes in. These unique identifiers enable you to pick specific rows in an entity set, as well as define their relationships to rows in other entity sets, allowing your database to handle complex computations.


Let’s explore keys in DBMS (database management systems) in more detail, before digging into everything you need to know about the most important keys – primary keys.


Understanding Keys in DBMS


Keys in DBMS are attributes that you use to identify specific rows inside a table, in addition to finding the relation between two tables. For example, let’s say you have a table for students, with that table recording each student’s “ID Number,” “Name,” “Address,” and “Teacher” as attributes. If you want to identify a specific student in the table, you’ll need to use one of these attributes as a key that allows you to pull the student’s record from your database. In this case “ID Number” is likely the best choice because it’s a unique attribute that only applies to a single student.


Types of Keys in DBMS


Beyond the basics of serving as unique identifiers for rows in a database, keys in DBMS can take several forms:


  • Primary Keys – An attribute that is present in the table for all of the records it contains, with each instance of that attribute being unique to the record. The previously-mentioned “ID Number” for students is a great example, as no student can have the same number as another student.
  • Foreign Key – Foreign keys allow you to define and establish relationships between a pair of tables. If Table A needs to refer to the primary key in Table B, you’ll use a foreign key in Table A so you have values in that table to match those in Table B.
  • Unique Key – These are very similar to primary keys in that both contain unique identifiers for the records in a table. The only difference is that a unique key can contain a null value, whereas a primary key can’t.
  • Candidate Key – Though you may have picked a unique attribute to serve as your primary key, there may be other candidates within a table. Coming back to the student example, you may record the phone numbers and email addresses of your students, which can be as unique as the student ID assigned to the individual. These candidate keys are also unique identifiers, allowing them to be used in tandem with a primary key to identify a specific row in a table.
  • Composite Key – If you have attributes that wouldn’t be unique when taken alone, but can be combined to form a unique identifier for a record, you have a composite key.
  • Super Key – This term refers to the collection of attributes that uniquely identify a record, meaning it’s a combination of candidate keys. Just like an employer sifting through job candidates to find the perfect person, you’ll sift through your super key set to choose the ideal primary key amongst your candidate keys.

So, why are keys in DBMS so important?


Keys ensure you maintain data integrity across all of the tables that make up your database. Without them, the relationships between each table become messy hodgepodges, creating the potential for duplicate records and errors that deliver inaccurate reports from the database. Having unique identifiers (in the form of keys) allows you to be certain that any record you pull, and the relationships that apply to that record, are accurate and unrepeated.



Primary Key Essentials


As mentioned, any unique attribute in a table can serve as a primary key, though this doesn’t mean that every unique attribute is a great choice. The following characteristics help you to define the perfect primary key.


Uniqueness


If your primary key is repeatable across records, it can’t serve as a unique identifier for a single record. For example, our student table may have multiple people named “John,” so you can’t use the “Name” attribute to find a specific student. You need something unique to that student, such as the previously mentioned ID number.


Non-Null Values


Primary keys must always contain a value, else you risk losing records in a table because you have no way of calling upon them. This need for non-null values can be used to eliminate some candidates from primary key content. For instance, it’s feasible (though unlikely) that a student won’t have an email address, creating the potential for null values that mean the email address attribute can’t be a primary key.


Immutability


A primary key that can change over time is a key that can cause confusion. Immutability is the term used for any attribute that’s unchanging to the point where it’s an evergreen attribute that you can use to identify a specific record forever.


Minimal


Ideally, one table should have one attribute that serves as its primary key, which is where the term “minimal” comes in. It’s possible for a table to have a composite or super key set, though both create the possibility of confusion and data integrity issues.


The Importance of a Primary Key in DBMS


We can distill the reason why having a primary key in DBMS for each of your tables is important into the following reasons:


  • You can use a primary key to identify each unique record in a table, meaning no multi-result returns to your database searches.
  • Having a primary key means a record can’t be repeated in the table.
  • Primary keys make data retrieval more efficient because you can use a single attribute for searches rather than multiple.

Functions of Primary Keys


Primary keys in DBMS serve several functions, each of which is critical to your DBMS.


Data Identification


Imagine walking into a crowded room and shouting out a name. The odds are that several people (all of whom have the same name) will turn their heads to look at you. That’s basically what you’re doing if you try to pull records from a table without using a primary key.


A primary key in DBMS serves as a unique identifier that you can use to pull specific records. Coming back to the student example mentioned earlier, a “Student ID” is only applicable to a single student, making it a unique identifier you can use to find that student in your database.


Ensure Data Integrity


Primary keys protect data integrity in two ways.


First, they prevent duplicate records from building up inside a single table, ensuring you don’t get multiple instances of the same record. Second, they ensure referential integrity, which is the term used to describe what happens when one table in your database needs to refer to the records stored in another table.


For example, let’s say you have tables for “Students” and “Teachers” in your database. The primary keys assigned to your students and teachers allow you to pull individual records as needed from each table. But every “Teacher” has multiple “Students” in their class. So, your primary key from the “Students” table is used as a foreign key in the “Teachers” table, allowing you to denote the one-to-many relationship between a teacher and their class of students. That foreign key also ensures referential integrity because it contains the unique identifiers for students, which you can look up in your “Students” table.


Data Retrieval


If you need to pull a specific record from a table, you can’t rely on attributes that can repeat across several records in that table. Again, the “Name” example highlights the problem here, as several people could have the same name. You need a unique identifier for each record so you can retrieve a single record from a huge set without having to pore through hundreds (or even thousands) of records.


Best Practices for Primary Key Selection


Now that you understand how primary keys in DBMS work, here are some best practices for selecting the right primary key for your table:


  • Choose Appropriate Attributes as Candidates – If the attribute isn’t unique to each record, or it can contain a null value (as is the case with email addresses and phone numbers), it’s not a good candidate for a primary key.
  • Avoid Using Sensitive Information – Using personal or sensitive information as a primary key creates a security risk because anybody who cracks your database could use that information for other purposes. Make your primary keys unique, and only applicable, to your database, which allows you to encrypt any sensitive information stored in your tables.
  • Consider Surrogate Keys – Some tables don’t have natural attributes that you can use as primary keys. In these cases, you can create a primary key out of thin air and assign it to each record. The “Student ID” referenced earlier is a great example, as students entering a school don’t come with their own ID numbers. Those numbers are given to the student (or simply used in the database that collects their data), making them surrogate keys.
  • Ensure Primary Key Stability – Any attribute that can change isn’t suitable for use as a primary key because it causes stability issues. Names, email addresses, phone numbers, and even bank account details are all things that can change, making them unsuitable. Evergreen and unchanging is the way to go with primary keys.

Choose the Right Keys for Your Database


You need to understand the importance of a primary key in DBMS (or multiple primary keys when you have several tables) so you can define the relationships between tables and identify unique records inside your tables. Without primary keys, you’ll find it much harder to run reports because you won’t feel confident in the accuracy of the data returned. Each search may pull up duplicate or incorrect records because of a lack of unique identifiers.


Thankfully, many of the tables you create will have attributes that lend themselves well to primary key status. And even when that isn’t the case, you can use surrogate keys in DBMS to assign primary keys to your tables. Experiment with your databases, testing different potential primary keys to see what works best for you.

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Computer Science and Cloud Computing: What Skills Are Needed for the Future
OPIT - Open Institute of Technology
OPIT - Open Institute of Technology
Oct 20, 2025 6 min read

More and more students are turning to careers in computer science, and it’s easy to see why. The world is becoming increasingly reliant on and powered by modern technology with every passing day.

Emerging innovations like artificial intelligence (AI) and cloud computing are set to change the face of countless industries. This means qualifications in computer science unlock the doors to countless job opportunities.

However, this is also a dynamic and rapidly changing field – a field that demands a distinct set of core skills to not only achieve success, but also future-proof your career for years to come.

The Importance and Value of Computer Science and Cloud Computing Qualifications

Official statistics show that the European cloud computing market is set to experience an astonishing compound annual growth rate (CAGR) of almost 23% in the coming years, moving from a value of €110 billion in 2024 to a lower-end estimate €250 billion by 2028, and it won’t stop there.

The same sort of growth is being seen across the full spectrum of computer science fields and industries, with emerging technologies like AI, automation, and edge computing all spearheading the surging value and importance of these sectors.

The increasing shift away from conventional computing towards cloud computing shows just how quickly the technological world changes and evolves. It also demonstrates the need for professionals with a wide and varied range of skills, plus the ability to adapt to rapidly changing situations.

Those who can bring these skills to the table, supported by a comprehensive education and effective computer science qualifications, can enjoy:

  • Entry into job markets that have exceptionally high levels of demand.
  • Diverse career opportunities in fields that range from AI and machine learning to computer engineering and software development.
  • Competitive salaries, with consistently high rates offered all around the world.
  • Job security and stability, given the ever-increasing significance of technology in the modern world.

Core Skills to Master for Long Careers in Computer Science

Next, let’s look into the actual specific skills that computer science students and aspiring leaders will need to master to secure their futures.

Programming Languages

Being able to work with code is the bedrock of almost any career in computer science. Aspiring scientists will need to master one or several programming languages, including Java for building business and web apps, Python for web development, and C++ for system programming.

Networks and Architectures

Computer scientists also need a strong core knowledge of the fundamentals of the computing world, like how networks function, the various protocols and architectures that control the flow of data from device to device, etc.

Algorithms and Data

Algorithms play a fundamental role in fields like AI and machine learning, so computer scientists must understand how different algorithms and data structures drive computing processes, problem-solving, and development.

Software Development

Computer scientists may spend much of their time working on development projects post-graduation, which may include apps for the web, business, mobile, and more. A strong understanding of the stages of the software development lifecycle and processes involved is, therefore, essential.

Cloud Computing

With cloud computing growing in importance, unlocking whole new fields, like software as a service (SaaS) and desktop as a service (DaaS), the computer scientists of tomorrow will also need to have intricate knowledge of how cloud computing works and the potential it holds.

Soft Skills

Along with the many technical skills listed above, computer scientists will also benefit from vital soft skills that will help them when collaborating with others, presenting their ideas, driving innovation in their chosen fields, leading teams, and managing projects. These skills include:

  • Being able to communicate effectively, both with fellow computer scientists and non-technical audiences as well
  • Analytical thinking and problem-solving skills that help scientists understand and respond to challenges
  • Adaptability, so that scientists can keep on learning, evolving their skill sets, and embracing new tech and ideas as they emerge
  • The ability to work as part of a team, often fundamental for large-scale computing projects
  • Attention to detail that allows you to spot that single line of code that needs fixing, or for tasks like debugging and data interpretation

Get the Best Start With a BSc in Computer Science at OPIT

We’ve seen the skills you need to succeed in computer science and cloud computing for years to come, but one question remains: where is the best place to gain these skills and acquire the necessary knowledge for genuine long-term success?

The answer: the Open Institute of Technology (OPIT).

An exclusively online learning platform specializing in computer science and digital business, OPIT offers a curated collection of online degrees for tomorrow’s technology leaders, including a Foundation Program for beginners, bachelor’s programs, and master’s degrees for the most experienced students.

Why Study at OPIT?

Advantages of studying with OPIT include:

  • Accessible and flexible online learning to suit your needs and pace
  • A focus on real-world applications of the skills and knowledge imparted
  • A leading team of top tutors and professors from diverse fields and nations
  • An international community of students with which to collaborate
  • Progressive assessment of skills and knowledge, as opposed to exam-heavy schedules

Those planning pathways into computer science and cloud computing are best served by OPIT’s BSc in Computer Science program.

Lasting six terms and worth 180 ECTS credits, this fully remote, online, and accredited undergraduate degree was developed with insights from industry leaders, academics, and employers within the IT industry.

It equips graduates with both the fundamental theoretical knowledge they need to succeed in technology, as well as the practical skills required to enter the world of work and immediately innovate in fields like programming, cybersecurity, data science, AI, and cloud computing.

Like other courses and programs available at OPIT, this BSc in Computer Science provides students with a flexible learning program involving a mixture of recorded and engaging live content, progressive assessment, fast-track options for those who study at a faster pace, and round-the-clock accessibility to tutors and fellow learners.

If you feel that computer science or cloud computing is the right path for you, and you want to secure the foundational skills you need to succeed, consider the OPIT BSc in Computer Science to help you achieve your dreams.

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My Journey Into Responsible AI at OPIT: Inauguration Day & Why I Chose This Path
OPIT - Open Institute of Technology
OPIT - Open Institute of Technology
Oct 20, 2025 6 min read

On September 8, 2025, the Open Institute of Technology (OPIT) officially inaugurated its 2025/26 academic year, welcoming a whole host of new students into the institute, ready to gain the skills and knowledge they need to be the tech industry leaders of tomorrow.

Faculty members, guest speakers from around the world, and hundreds of students from over 100 nations were all in attendance at the online inauguration event. Among them was one new student on the MSc in Responsible AI program: Rem Lampa, also known by his online alias, Kuya Dev.

A Filipino podcaster, speaker, and developer, Kuya Dev documented the inauguration experience in a YouTube video, sharing his thoughts on the event. Here’s a detailed look at his experience, showing the welcoming and effective way in which new OPIT students are brought into the institute from the first day.

An Overview of the Inauguration Event

The latest OPIT inauguration event was one to remember, with the institute celebrating several notable milestones. These included the first graduation of the MSc in Applied Data Science and AI program, and the unveiling of new industry connections and corporate partners offering opportunities for graduates.

Various guest speakers were in attendance, including the former Italian Minister of Education and current OPIT Rector, Professor Francesco Profumo, plus the CEO of Malta’s accreditation authority MFHEA, Dr. Rose Anne Cuschieri.

OPIT founder, Riccardo Ocleppo, also took to the stage to highlight the transformative role of education and the unique possibilities offered by the online-only OPIT degrees, stating:

“When we launched OPIT in 2022, we wanted to prove that an online degree could be rigorous, international, deeply connected to the world of work, and engaging. Three years later, we can already see results. This year alone, 300 new students are joining us, representing 98 nationalities.”

Those hundreds of new students were also, naturally, in attendance for their big inauguration day, welcomed into the institute’s various BSc and MSc programs in specialties like Computer Science, Digital Business, Digital Business and Innovation, and Cybersecurity.

Introducing Rem ‘Kuya Dev’ Lampa

As mentioned, one of the new students joining was vlogger and podcaster, Kuya Dev.

Already boasting extensive experience and technical expertise in the computing world, Kuya Dev has founded several tech communities, including Tech Career Shifter Philippines and Server-Side JavaScript.

He describes himself as an advocate for responsible AI and tech practices, and once gave a powerful TEDx talk about the negative potential impacts of artificial intelligence (AI), including its large carbon footprint and involving exploitation of workers in emerging nations. So, it was only fitting that he signed up for OPIT’s MSc in Responsible AI.

The MSc in Responsible AI Program

A postgraduate program lasting three or four terms (between 12 and 24 months, total), OPIT’s MSc in Responsible AI is an accredited program that combines technical skills with a core focus on the ethical implications of AI technology.

It explores real-world use cases of AI and ways in which this exciting and powerful technology can be used responsibly and sustainably, emphasizing its potential for both positive and negative change in areas such as the environment and society as a whole.

Students of this program enjoy all the usual benefits that come with studying at OPIT, like flexible-paced learning, tutors available on a daily basis, a dynamic and engaging online learning environment, and fair, progressive assessments over time.

Those who graduate can move into careers in AI Application Development, AI Research, and AI Business Consulting.

Highlights and Impressions of Kuya Dev’s Inauguration Experience

Inauguration is always a special moment in any student’s academic journey as they take their first tentative yet exciting steps towards new knowledge and skills that can unlock their potential and accelerate their development.

It can even be a “make-or-break” moment in which students can either feel welcomed, empowered, and eager to begin their studies, or, conversely, experience feelings of worry, doubt, or regret if the inauguration lacks the spark they were hoping to feel.

Fortunately, Kuya Dev and his many fellow new OPIT students had a very positive experience at the inauguration event, with the vlogger calling it both “very fruitful” and “very insightful.” Some of the specific highlights he mentioned included:

An International Community

Early in the inauguration event, Kuya Dev heard from Professor Francesco Profumo about how OPIT was welcoming students from over 90 countries.

This, for Kuya Dev and for so many other students, is one of the big perks of studying with OPIT. It allows students to meet, engage, and exchange with people from dozens of different backgrounds, cultures, and communities, learning new ways of thinking and collaborating.

Real World Applications

The OPIT inauguration also focused on another of the university’s key features: a focus not merely on imparting knowledge to students or making them memorize facts, figures, and theorems, but actually teaching them how to apply that knowledge and ideas to real-world uses.

Kuya Dev commented on how other universities that he had considered attending appeared more conventional and limited in their approach, and also shared his excitement and enthusiasm at OPIT’s unique approach, focusing more on genuine industry collaboration and real-life scenarios.

Inspiring Speakers

The vlogger and podcaster also commented on the various key speakers who hosted the event. He was pleased to see that they were not only academically oriented but also all had real-world experience and a diverse range of working backgrounds in fields like politics.

This, too, is part of what makes OPIT different. It features a winning team of international tutors, professors, and experts from diverse fields, including the aforementioned former Italian Education Minister, education executives, research chairs, digital content creation specialists, and more.

Graduate Experiences

Finally, Kuya Dev noted how several OPIT graduates spoke to those about to follow the same path they did, including students from nations as diverse as the U.S., Italy, and Nigeria.

They all shared their experiences and detailed what they enjoyed most about studying with OPIT, including key factors such as professors who took the time to get to know their students, as well as the depth of the topics and knowledge covered in each course.

A Successful First Step Into OPIT Education

All in all, the recent inauguration event was a major success for all involved, giving students like Kuya Dev the ideal introduction to life and study with OPIT. He, like so many of his new fellow students, left the event eager and excited to expand their knowledge and broaden their horizons in unique ways that only OPIT can provide.

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