Entity-Relationship Diagrams: Simple student registration system example 

Thanks!

Lucidchart.com

what engineer?

Data Engineer, I guess. If there is even such a thing...

@@notahamster333 software, computer, cyber secuirty engineers etc need basic database knowledge and have it in their curriculum, you dont need to be a 'data engineer' to know how to use SQL, set up a database for your site, avoid sql injections etc. And ER diagrams are the foundation of all of these

Yep, this is lucidchart.com. I like it because you can also export the SQL CREATE scripts to generate the database. Many programs will do that though

@@MarkKeith Thanks u 🤍

Good question...well, it depends on what rules you want to follow. For example, can an instructor teach in multiple departments? If you want to just keep things simple, I would connect the department class to "Course" since a course is likely to below to only one department. Then you have a simple one-to-many from department to course. Depending on what rules you need to follow, you could also connect department to the instructor class. But, then you need to find out if instructors are allowed to belong to multiple departments. If not, then it's just another one-to-many from department to course. If they are, then you'll need another one of those "association classes" or "linking tables" (whatever your instructor wants to call it) between department and instructor. Good luck!

That’s true; it all depends on the rules you want to enforce and whether the DBMS will allow that or not.

Mostly, but not completely. I probably could have removed classroom and date/time into their own tables. There are 5ish or so normal forms and usually we find a balance between not normal and fully normal. Generally speaking, most would say this example is “normalized”

No, just the free education account

Primary key - the unique identifier of teach row in the table

Logical ERD

I’m using lucidchart.com to generate the diagram

It's a website. google Lucidchart

@@ZenAzou THANK YOU MA FRIEND .