Database Lesson #4 of 8 - Data Modeling and the ER Model 

Dear Dr Daniel I just wanted you to know That I am a computer science student who lives in Syria With very Poor financial conditions so I cannot afford for private tutors to teach me dbms I'm so grateful for the high quality knowledge you provide here for free Words cannot describe how thankful I am Wish you all the best

Requirements to ER model 5:15 Entity class v entity instance 6:50 Entity class v entity instance visual 10:30 Attributes 11:20 Identifiers [keys] 13:10 Types of keys 13:50 Level of entity attribute display 16:45 Relationships 18:50 Conceptual unary relationship 21:20 Conceptual binary relationship Conceptual ternary relationship One or many connections 23:12 One-to-one binary relationship 24:10 One-to-many binary relationship 25:00 Conceptual many to many binary relationship Note: can’t build a direct conceptual many to many in a db. Need a middle table….extra entity 25:40 Conceptual many to many binary relationship/ extra entity 26:50 Maximum cardinality 27:20 Minimum cardinality 28:40 Crows foot symbols 29:20 Cardinality example 33:20 Er diagrams 34:40 Has -a-relationship 36:00 Strong and weak entities 36:30 Id-dependent weak entities 38:00 Weak entity relationships 40:00 Weak entity identifier/ non-id dependent 41:30 42:10 Subtype entities 44:00 Subtype entity identifiers 47:30 Subtype entity examples Recursive relationship 53:00

You're better than my prof. I've been anxious about this class because the lectures cover just spouts of info and not the details. Thanks for this!

Paying 9 grand for uni and get a useless pdf as a resource. Pay nothing for an hour long, detailed, easy to understand video. This is just so wrong

Thanks a lot Dr. Soper, best coverage on the data modeling and the entity-relationship (ER) model I have ever seen. You are one of the best teacher I have ever had.

Dr. Soper, you are a great teacher. The content is so clear and easy to understand, the way you explain things is so logical, and your examples really help. Thank you for this!

Thank you so much Dr Soper; this is hands down, the best ERD tutorial I've ever watched. Great job!

I've taken 2 database classes in the past but I've learned so much from your series of videos than I've learned in the classes, very detailed and easy to understand, thx u so much.

If it must be done, It must be done well. Dr. you did it all . from simplicity through clarity to comprehensiveness. Bravoo!!!!!

Love everything about your lectures - the pace, the material, the structure, presentation and also the manner of speaking. Huge thanks!

Dr. Daniel Soper, thank you so much for this. This is by far the most clear, lucid explanation of data modeling and ERDs I've come across. Fantastic!

Your method of presentation is second to none and your explanation is top notch. You deserve an award. Thank you!

Just came across your tutorials today after years of many challenges learning databases. I'll return to give feedback. Very positive comments so far about your work. Thank you

Very clear and concise. Video elaborates on specific details that are critical to understanding the subject matter. A+ quality. Deeply appreciative of your generosity!!!

Saved the video in 2018 and watching in 2022. What a gem! Thank you so much, prof.

This is a great addition to my non-lecture database class. I will recommend it to my class. Thank you.

This is the best tutorial on this topic you'll find on the internet

a joy to refresh and learn with Dr. Soper. Thank you!

At 20:56 I was having difficulty with the Person entity relating to itself with marriage. I was thinking “Aren’t 2 different entities getting married?”. Then I resolved the difficulty by realizing that A person entity is a table. While an employee table relating to a parking table is a binary relationship because it involves two tables, one person instance getting married to another person instance is a Unary relationship because it involves just one table which is why we also call it a reflexive relationship.

37:07 "Any entity that is not a weak entity is called a strong entity" Very helpful.

this is the best video on Data Modeling . very clear and explanatory. well done prof.

I thank God for creating people like you.

This is gold. The best lessons on RU-vid.

Dr. Soper thank you for this great video series.

Very smooth and understandable explanation. Thanks a lot.

Thank you Dr. Soper for this presentation. It has been a great help!

Thank you Dr Soper. This is really amazing. God bless you.

I have studied all those things at the university and I had no idea what the heck I was studying. I could barely get B0 (B-) for all preparing tests and exams with many not sleeping nights. I was just happy not to get FAIL. I have been watching this video with 1.5X speed and can't believe everything is so well explained and easy to understand!)

You have a teaching gift - like many others who have furnished a response - I currently study this topic at University. The teaching at my facility just isn't up to this standard when it comes to imparting concepts this clearly...I am almost at the end of your fourth video and feel I have such a good grasp of the concepts involved. Thank you

Thank you so much Dr. Daniel Soper.

I have no formal training on IT.yet these lectures give me an insight into the IT world...Thanks...from Nepal.I am learning a lot...

Thanks a lot Dr. For this really informative lecture. Have a good day

That is is great lecture I ever had before. Thanks very much Dr. Soper.

Dr. Soper, this is excellent. Thank you very much.

I appreciate your careful systemic explanation

Thank you for these videos, they have been incredibly helpful.

Valuable learnings keep life FRESH😊 Thank you for your valuable lessons🙏

Why hasn't my prof done anything like this? I'm having to scour the internet to find a lecture on the subject. My professor just has us read the book, then gives us assignments. He offers no other learning resources whatsoever. Thankfully I've found this.

Very useful.. Explaining it in a very simple way.. Thank You Dr. Soper.

Great presentation; well-spoken and thoroughly informative. Will definitely utilize your videos to supplement my AIS course!

Thank you for this amazing lecture series! One feedback- I'd love to see more examples of how to read the diagrams depicting entity relationships- You explained the concept well but some more examples would help the viewers

Dr Soper.. thank you very much for knowledge.. u made things so simple ..wow :)

Thank you so much Dr.Daniel Soper, this is the best use full and understanding lecture I never had i'm thank full! if you have more continuing database lesson 9 Ext

Excellent. Explanation is so simple and effective.

Dr. Soper you are a life saver

Great,perfect explanation.One of the best video tutorial in the youtube I have seen,I improved my Englilsh also as an extra benefit.

Amazing series Daniel! Thank you very much

Thank you so much Dr. Soper!

Thanks god for a video in RU-vid I can understand

I am very stoked on these videos.

I took introduction to Oracle SQL and this is bringing it all together for me.

Writing business systems and analysis test in 12hours, thanks to Doc im gonna nail it

Thanks for all you do;

Very informative lecture . i was able to understand the data modelling in much better way. Thank you sooo much for making such a great video with great explanation. :)

Thank you for this presentation, this was very helpful.

Great work on the video series. Very informative.

You are an awesome teacher!

Awesome vid! Now I understand the giant 20-30 entity diagrams in my work.now All I have to do is memorise them!

Great man done great Job. Thanks Dr. Soper

Well done, Dr. Daniel Soper.

Thanks a Million Professor!!!! God bless you.

Thanks for the excellent presentation!

Thank you Sir. This is still relevant and informative in 2019

wow, in this way (and length) every youtube video lesson should be. Nice!

that's really amazing God bless you

very well explained Data Modelling and Entity Relationship Model. Thank you

Thank you Dr. Soper!

Awesome series. Thanks so much!

*DR. SOPER* , I am learning a great deal from your lectures! I believe I found a small mistake at 52:52 and 55:03. In the recursive (unary) relationship between employees and managers, an employee need not have a manager (e.g., the CEO has no manager), but each manager must supervise at least one employee _and may supervise many employees._ So, the crow's foot symbol next to the employeeId attribute should have a cardinality of *one-to-many* , not one-and-only-one. Is that correct? Thank you!

thank you dr for this amazing content

Great Videos and Very informative for building good concepts. Thanks.

Thank you so so so much!!! My textbook is written poorly. Also, I now even understand objects and classes better. Thanks!!!

Very helpful! Thanks a lot for sharing!

very very useful, and easy to understand and in easy language. thanks

very nice video! thank you for taking the time to share your knowledge. However, I had to speed up to 1.5 as i found it to slow but that is probably because i had too much coffee. Works like a charm

Thank you. Very well explained.

Thank you for the lesson!

Great presentation. Thank you

Thank you for the video.

Great Lecture

Thanks, Professor.

Excellent presentation

thank you very much !! very clear tutorial

great explanation!

Great videos!

great presentation it was helpful

I gave you a like for using Fry, Leela, and Bender!!!

i learned alot! Thanks :)

Very helpful teaching presentation, above all I admire your good intention for sharing it with the public. Is there any other subjects or topics on your agenda? - Thank you.

Thank you Professor

The guy is great!

Perfect!

great video.

This series was highly recommended to supplement my DBMS course....but that microphone static in this video is incredibly distracting.

Great information about databsa

Thanks very much for your lecture. I was able to connect a lot of dots. Would you post the slides - the examples help when trying to model parallet db schemas in my own work. Thanks again.

Thank you!

superb!

Question: If the PK of the strong entity is not a FK in the weak entity, and all other restrictions remains the same, would it be a non-id-dependent relationship?

I will remember you as Dr. Daniel "Super".