So what are all the differences with all these databases?
I mean, I've only shown you a few of the options as we have for databases.
There are hundreds of options, for example, if I search database management system.
I'll probably get a list of database management system, let's do Wikipedia here.
All right, so database management systems, as you can see, there are a lot of them.
Once again, we should understand this, if we go to database's, we got a list of databases or lists
of database management systems.
So let's look at the list of database management systems.
And again, there are a ton.
Now, if we click on, let's say, the first link, yeah, that's a lot of databases.
Now, you're never going to use all these databases throughout your career, you'll probably touch a
few, just probably less than five.
Most people might just have two or three databases that they work with.
But you can categorize databases into five main types, these five main types of databases.
I'm not going to go into full detail because you need to learn more about databases before you truly
understand their differences.
And later on in the course, it will actually cover some of the differences between databases and learn
about some interesting popular databases that are out there.
But for now, let's talk about the five kinds often called the five data models.
One is the relational model.
This is one of the most popular ones.
This is the one that we kind of saw with my school.
And PostgreSQL, they support something called asset transactions.
Sounds complicated, will dive into what that is.
But popular databases like postgrads, like MySQL, Microsoft's SQL Server all use this relational model
and it's probably the most popular.
And this relational databases work really, really well with escudo.
So you'll see these types of databases and a lot of e-commerce websites, a lot of websites that have
customers or users inside of businesses.
They have a lot of applications and in the scores who are really going to dive deep into relational
databases.
Next is a document model, a document model database.
You may have heard of things like Mongo, DB, Couche, DB or FIREBASE.
They use what's called a document model.
And in this case, data is almost in a document rather than rows and columns like we saw in the Amazon
exercise.
These databases are usually a big document that contain a ton of related information.
Together, these types of databases are usually really, really good at what we call scalability databases
that have to hold more and more data that have to be more and more performant.
We'll talk about the differences between these types of databases and document databases, because it's
a popular topic.
You may have heard of PostgreSQL versus Mongo DB We'll have a video on that later on.
Then we have key value databases.
Now, you may have heard of things like retests at CD or Dinamo DB.
These are key value storage systems.
It's a model that is one of the simplest ways to access data.
You essentially have a key that is, hey, I want to get user ID one and you get to user ID one back.
We're going to have a section on Radice in the course.
We can learn how a key value database might work.
Then we have graph model databases.
These are databases like Neo for or A.W..
Yes, Neptun.
These types of databases are a lot rarer because they're a little bit more complex and they use something
called a graph model.
That is, it's really good for data that is connected in different ways.
It's all about relationship between different units.
So a social network website might have graph databases because they want to see how different users
are connected to one another.
Out of all of these graph databases are probably one of the least used because they are so specific.
And then finally, we have something called wide columnar model.
These wide columnar models are fairly new and they were pioneered by Google's big table databases like
Apache.
Cassandre, Google's big table are very popular now, all linked to a resource.
If you want to dive a little bit deeper into what these differences are.
But I recommend to hold off on that until you are done with the course, because a lot of these are
new topics that might be hard for you to understand.
Ideally, you finished the course.
We explore some of the relational document key value databases, understand what their differences are,
what the pros and cons are, and then you can dive deeper and deeper.
But I wanted to just mention it briefly here, because with this course, the goal is to get you comfortable
with school, with the idea of databases and so that you are able to make decisions on when to use what
I'll see in the next one.
But by.