Class Database Design Course Learn how to design

Class Database Design Course Learn how to design
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 I never really explained  why well this video I’m going to explain why. Think of let’s think of a good example  a. College  can have many students and a student can have many . So we have  two entities we have to worry about.  We have a  class.  Let’s just pluralize it because it makes more sense the and then the  students.  So let’s just think of an example of a way we would try to treat we would try to design  this, and it’s not gonna work out, right, but we’ll just we’ll just try. Here we have   table, and we have a specific class such as math,

Student

 Whatever really so we have Matte we can’t even read that my handwriting is so bad. So we have math one  on one. And then we list all of the people within this class. So we have student number  one. And then student number two. And then student number three. All right well we  can try that. Except what if a student drops out Well then we have a null value, which  we don’t want to have those if possible. And what if we need four students? Well, that’s  not going to work because we only have three columns.

Column

So how else can we do it? Well, we  can try just having students. Well, then every single column could have like 100 students,  and we already learned about the atomic rule, we only want one column to store one value  one student. So what do we do? Well, okay, that’s not gonna work. Let’s try over here.  Let’s try it on the student side. We have a table for students. So we have Jimmy, and  he’s taking his first. Alright, let’s let’s list the columns. So we have the name. And  then we have class number one. And then we have class number two. And then we have class  number three.

 

 

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