Before learning about databases, let’s first discuss what data is. Think about it for a moment. What do you consider data to be? Take your time to think.
Now, in your mind, you’ve probably thought about some examples of data. Let me also give an example from my experience. My first day of school started with an admission process at the school’s office. My father gave them my name, my age, his name, our address, my birthdate, my religion, my blood group, and other details. With that, I became a student of that school. A few months later, I took some exams and received different marks in different subjects. At the end of my first year, I was given a rank based on my performance in all subjects.
I gave this example because it’s a real-life experience most of us have faced. All the details I provided during my admission are data. After a few months, my school updated and added more data to my record. Then, after one year, I was able to look back at all the data collected about me throughout the year.
Almost everywhere, we generate data. It could be the name of a car, its color, its price, someone’s location, their skin color, etc. Not all data has to be valuable to everyone. For example, my birthdate may not add any value to you, and you probably wouldn’t be interested in it. However, Facebook takes our birthdate and uses it to send birthday wishes and notify our Facebook friends.
Now, we have a clear idea of what data is. But how does Facebook remember our birthdays each year?
For this, we need a database, which stores data. In ancient times, knowledge and innovations were scripted in books, and these books were kept in libraries where we could find relevant information. However, extracting data from books could be difficult. In contrast, if you search for a friend named “Rayan” on Facebook, it instantly provides you with the correct profile. This is because a database stores relevant data about users.
For Facebook, your exam results are not important, but they are important to your school. Conversely, who your friends are might be important to Facebook but not to your school. Data is everywhere, but it needs to be organized.
If I store the names of 10 people along with their ages, that is also a database. Similarly, any collection of data, whether small, large, or complex, that is structured becomes a database. Whenever we request some information, the owner of the database returns the expected result. For example, if a bank’s database is lost, the bank wouldn’t know how much money you have in your account.
A database is created using rows and columns and is stored in a computer system. Data can be stored on computers, mobile devices, or even in the cloud. There are different types of databases:
- Relational Database: Data that has relationships with other data. Example: MySQL, PostgreSQL.
- Distributed Database: A database that is stored across different locations.
- Cloud Database: A database stored in the cloud. Example: Amazon RDS.