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Reminder: first name, last name, and email is not a Candidate Key because we can reduce the key to email

Superkey is every possible key out there the ones that can be reduced
and the ones that cannot be reduced. The keys that can't be reduced get
elected as Candidate keys and then ONLY one of those candidate keys can
be selected as a primary key. For example, "First Name, Last Name, Email" is a superkey but cannot be a Candidate Key. However, Email is a Candidate Key because Email is unique enough to identify a record without the need of first name and last. In short, First Name, Last Name, Email is superkey not a candidate key.

Note: In the first five seconds, the voice sounds as if it got cut in half when in fact its not. This problem was caused by audio issues.

Important Note: Fourth Normal Form is listed under lecture 124 by the very end of the Physical Phase; I didn't create appendix section. Why did I move 4NF to lecture 124? 4NF+ is more theortical and may confuse you and distract you if I demonstrated it right after 3NF. Also, 4NF and above are supplementary and not mandatory.

You can find lots of free youtube tutorials on how to design ERD on Microsoft Visio. For the time being, don't worry about designing ERD on MS Visio because it's luxury rather necessity. Anyhow, if still interested in MS Visio, here is few resources:

https://www.youtube.com/watch?v=K0mNzXnHkYc

https://www.youtube.com/watch?v=sIX80pvJnMY

https://www.youtube.com/watch?v=znzAYZhEsuU

https://www.youtube.com/watch?v=gW7xpykljeU

The HR example is supported and provided by Oracle Corp.

From 1:40 to 1:50 there was a video editing issue that may cause confusion:  

total salary sum of department 90 is 88,000 NOT 58,000

In this lecture, I added the keyword "CONSTRAINT" when assigning primary key and foreign key. Note that the "CONSTRAINT" keyword is optional. The fact is whenever you create a constraint such as primary key or foreign key, the Oracle system automatically gives each constraint a unique name implicitly; so, rather than letting Oracle assigning the constraint name automatically, you can use the keyword "CONSTRAINT" as shown in this lesson. How can assigning CONSTRAINT name help you? It helps you when you decide to drop the primary key or foreign key from a table! How would you identify the PK and FK to be dropped? You identify them through the CONSTRAINT name.

Comments regarding this video tutorial:

You do not necessarily have to enclose an alias with double quotation. The only time you are obliged to wrap double quotation on an alias is when the alias has spaces, such as First Name; you will have to write as "First Name". Also, the keyword AS is optional. You don't have to use it to name an alias.

Congratulations for the excellent effort you put in!

First of all, thank you for joining this training program. Secondly, I prefer all questions to be posted in udemy discussion platform, so your fellow students can learn too. There is no such thing called stupid question. All questions matter to me; ask and never feel shy! I'll be happy to help you out.

Reach me at my personal email fjamcom@gmail.com. 

http://www.FahmiEshaq.com