Hugh, welcome back.
Now, I know, I know I've been talking a lot and we've been staring at slides.
I know you want to start doing something.
You want to start writing.
Some ask you all queries and actually interacting with a database, which we're going to start to do
in the next video.
But hold on tight just a little bit more, because we just talked about all these databases.
It all looks kind of intimidating.
So let's wrap our understanding of databases in this lecture so that we can start doing some fun exercises.
So in order to complete our understanding or at least initially complete our understanding, let's talk
about some of the confusing terms you will hear throughout the course, because computer scientists
just love giving difficult names to not so hard concepts.
Now, in discourse, the way things are going to be structured is because we have data coming from all
over the world, all different places.
And when you work at a company, most likely a company already has databases set up.
We want to focus on three main things.
One is how to put data in a database.
Yes, we'll show you how to install a database on your machine, which you might do at a company.
Although very rare, we're going to learn how to put data in a database that already exists.
We're going to learn how to use update, learn from this data.
And we're also going to learn how to remove data, all using school.
But first, let's talk about these confusing acronyms that you're going to hear out in the wild and
also myself and most speak.
The first one is Debbie Asmus, or a database management system, a database management system is a
software.
It's a program that is used to manage the database.
It receives instructions from somebody like us that wants something to do with data and instructs the
system, the database to make this to actually grab the data or make changes to the data.
And then we have relational database management system.
This is a subset of database management system, what we're going to learn about is something called
relational databases, and they're the most used, the most common, the most popular type of databases.
And in my opinion, the most useful things like my school, askew light, PostgreSQL, Microsoft server,
Oracle, all use this relational database management system.
At the end of the day, it's the same thing as a DBMS is just more specific, saying, hey, this uses
a relational database model, something that we'll talk about shortly.
And then finally, why you're taking this course is QOL or a structured query language.
It's a way for us to interact with a database management system.
Now, all these words are a little bit confusing.
So let's use another diagram.
We have all this data coming in and this data coming in can be images, can be user profiles, can be
audio files, can be logs of information of statuses.
And we learned that we need to learn how to put this data in a database, how to use update, learn
from this data, and also possibly how to remove this data.
And in order for us to do this, we use those acronyms that we just learned about.
That is we have data.
So data which is being stored in a database.
We have a DBMS or RDBMS, remember, it means database management system, and we use something like
PostgreSQL, which is a relational database management system.
So again, a database management system usually gives us functions, basic ways for us to read data,
to create data, to update data more, to delete data often called crud operations and database like
postcrisis is what we call a relational database, which is why we use this hour at the beginning,
again, something we'll talk about later on in the course.
But a relational database is a database that allows us to set up connections among different data records.
And then finally, this whole picture of data combined with a data management system, a database management
system, is what we usually call a database.
You see, when you hear things like my ask you all, PostgreSQL, Cassandra, Maria, DB, Coach, DB,
Cockroach, DB, all of these things are actually software or database management systems, a way for
us to store data but also interact with this data.
So when we refer to a database, we essentially mean these things.
But at the end of the day, when you hear postcrisis or miscue, all those are all just database management
system, a way for us to interact with this data.
And then finally, we have secure the structured query language.
It's not really a programming language, it's a query language where ask you, well, its role is to
give us the ability, like all the people that we saw, like product managers, like business analysts,
like data engineers, like web developers to communicate with these databases using a very simple language
school that is very English like.
And anybody can use a very simple thing once you learn its rules and interact with all these database
management system.
Now, in here, I have postcrisis as an example, and we'll use PostgreSQL in discourse because it's
one of the most popular databases.
But the beauty is that when you learn you well, it doesn't just work with one database management system.
If you remember our diagram by learning, you will we get to interact with a lot of databases because
a lot of these databases, not all, but a lot of them, like Maria DB, like Microsoft SQL Server,
Oracle Database, MySQL, Allied Postcrisis Skua, most big database engines are compatible with all
askew all code because they all say, hey, I want our database to be as easy as possible for people
to pick up because we want people to use our database.
So they use the actual standard and they implement in their software a way for them to understand these
all commands.
So once you learn school, it should be very familiar and similar for you to work across many databases.
This is the beauty of learning school that it gives you the power to work with multiple types of databases,
no matter what your role is, and later on in the course will even show you how to decide on different
databases.
But for now, that's a lot of talking for me.
I want us to start doing some exercises and actually learn what this whole school thing is about.
In the next video, I want us to create Amazon and learn about how they went from not needing a database
to using spreadsheets to finally implementing a database.
And we're going to write our first ask you all statements.
Let's have a look.