Relational Data Model

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In the previous blog post, we covered Data Modeling. We have seen that data modeling is really important before jumping into predictive modeling. 
In this article, we will cover the Relational Data Model (RDM).
Let's start from the very basics, relational means anything which is linked with some other thing. This link is called "Relationship". In RDM or RM there are major three types of relationship cardinalities (also called Multiplicities or Cardianalities):
1. One to one
2. One to many
3. Many to many

We can understand these with the help of a few simple examples; 

One to one: One department has one manager.

One to many: One class has many students.

Many to many: Many teachers can teach many students.

Okay, so we have got an abstract overview of the term "Relational", now the next thing is "Data", data covers everything, anything... And finally, "Model" means something in the form of a template, design, a kind of blueprint. 

To store the Relational Data Model, we use a Database management system called Relational Database Management system (RDBMS)

Now, that we have got data in the form of tables, we have got a management system to keep and manage our data.

What's next?

we can get insights from our data... Yayyyyy!! 

But wait, it's not that simple, there are basically two types of systems when it comes to databases. 

1. OLTP (On-Line Transactional Processing)

2. OLAP (On-Line Analytical Processing) 

If you are following my previous articles, then you might have got a little glimpse of these terminologies, if not then nothing to worry about, we will check these along with NoSQL data models in connection with a data warehouse in the next blog post.

Happy Learning :) 

 

 

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