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@Lordrich95 9 күн бұрын

Yes that exams has brought me here so help me God … Thanks to the Tutor !!

@CryptoKosh 12 күн бұрын

When we go for 4NF, we are now storing this data in multiple tables. Now, if our application needs to pull data from multiple tables, it will actually make the query slow when we go for a large data set. So its trade off between (high consistent and atomicity and low redundancy) Vs Performance For High performance you actually might need to denormalize them often.

@abc123evoturbobonker 26 күн бұрын

What happens if 'wilson44' buys another 'Xbox One' ?

@mjj2u2 Ай бұрын

Well done. Great examples.

@ravichandrasekara7907 Ай бұрын

great

@kennethkimathi7313 2 ай бұрын

The PK in the subscription table has repeating entries. How is that?

@lekhanhhuyen7402 4 ай бұрын

In Subscription table : there are 2 records with the same ID wilson44. The video stated that CustID is the PK, so this ID must be unique. I am confused.

@micmike 4 ай бұрын

Concise! Thanks

@smtxtv 5 ай бұрын

Yep. Great explanation. You uncomplicate what has been previously presented in a disjointed, convoluted manner. Thx ! What I needed, for sure.

@user-dp7lr5qh6o 6 ай бұрын

Thank you so much. After 8 years it is still helpful

@adilmughal2251 7 ай бұрын

one of the best explanations on database normalization.

@kodiq3429 8 ай бұрын

Thank you so much. Its first video out of 15 when I understand it

@GrantWill 8 ай бұрын

Your example for a 1st Normal Form table doesn't meet the requirement of rows being uniquely identified. Alan Smith could buy two Xbox Ones and ship them both to his address in Miami and there would then be two duplicate records. Needs an order id/qty column.

@user-qw6ho1co1p 10 ай бұрын

I have a question..? How can a Primary key column have repeating values? Is that possible? Like in the customer Table - Cust_ID = wilson44

@jpaxonreyes 4 ай бұрын

If I have the right idea, normalization is applied at the design level. Although wilson44 is duplicated and listed as a primary key, there is actually no table or database yet. The customer id is denoted as the primary key because that's how he wants to structure the database. He's still normalizing and everything gets fixed before implementing the design.

@awildpiizaroll 11 ай бұрын

Question: For 2NF, couldn't you make cust ID and Item a composite key that would determine all values in one table?

@jessemorningstar Жыл бұрын

Key correction at 18:40 👉 In the Subscription Table and Sales Invoice Table: Cust ID should be the foreign key not the primary key. The reason being is that values in a primary key column must not, and indeed cannot, be duplicated. wilson44 is duplicated in both tables. To fix this the Subscription Table and the Sales Invoice Table must declare a distinct column as the primary key. 👉 Giving each subscription and sale invoice a unique number will make every entry distinct.

@hanzalamansoor Жыл бұрын

Thank you so much, you saved my time searching for this topic and not been able to find a video with this much details. You also explained it better than my lecturer Which clear my concept about table normalization till 4 normal form. I request you to please make a video on 3.5 n.f as well . ❤ You earn a subscriber here 👍

@willardbarrwb Жыл бұрын

Hands down the greatest normalization example and explanation I have ever watched. He used one example straight through unlike others who like to switch the example once they reach 2nf and he explain partial dependency in layman terms than just textbook.

@andreamiljak9457 Жыл бұрын

bolji od papica

@junioralamu7438 Жыл бұрын

I thought 2nd normal form should be not partially dependent (composite key). It looks like you did 3rd normal form in your 2nd normal form since it is a transitive dependency. Or am I wrong?

@afkgamer7204 Жыл бұрын

pffffffffff And shipping Address??!!! Should not break it in Address and City??????!!!!! Atomic value??????????!!!!

@sjdkshfkjdshfk Жыл бұрын

nice

@williamstorey5024 Жыл бұрын

I want a xbox for 250 please. ill take everyone the you have

@mikeandrewfernandez9797 Жыл бұрын

Damn, you just made normalization easier. I was having trouble identifying dependencies but the way you explained it was as accurate and practical as hell. Thank you for this wonderful video!

@strawberrymochi3420 Жыл бұрын

1 add unique id, PK 2 check if all non key columns can be defined by PK, separate to 2 tables 3 no duplicated record, separate to entities 4 no multi value dependencies, non key columns relying on PK with duplicated records that are unable to be solved using new unique id. So, create new tables with PK+non key columns

@Icey-s Жыл бұрын

Thanks for the video, what are the disadvantages if we include Newsletter in Item table?

@aesthetic3810 Жыл бұрын

Why did you remove and add different values that's not exist in the old tables? Its confusing and also the primary key is unique and not null. Bro? enlighten me

@xitsjinxbtwx Жыл бұрын

I’ve come to the conclusion that I’m just stupid, because this still makes no sense. Thanks for trying though🙏🏾

@yasirzubair20 Жыл бұрын

Clearly explained throughout the entire KZbin platform!

@exitspree Жыл бұрын

Thanks for this video!

@sunilkumarkatta9062 Жыл бұрын

One doubt How Cust ID could be a primary key, as the attribute value wilson44 is repetative

@mzwandiledlamini4552 Жыл бұрын

For the first time I've seen someone explain this clearly than my lecturers at school.

@breezycodes Жыл бұрын

7 years later & this is still gold!

@davidsetiabudicomputerscie8683 Жыл бұрын

If you think my correction are correct, Sir. Please inform your viewer to watch here: kzbin.info/www/bejne/gXzCZp-wpq6ojZI Thank you and God bless you, Sir.😁

@fabimawn Жыл бұрын

Even though this video is 10 years old by now. It's the BEST explaination of a simple but effective implementation of objects that just works!!!

@justsaying4488 Жыл бұрын

Really good video

@DirectionNext Жыл бұрын

Thanks for creating this video. Simple, crisp and to the point with proper example. Amazing video.

@Life_truths-bt Жыл бұрын

I cudnt understand this in my whole academic period

@kakairecharles3474 Жыл бұрын

Too simplified. Many thanks.

@the_derpler Жыл бұрын

I wonder would it be worthwhile to add a `NewsLetters` table and then a junction Table like `Customers_to_Newsletters` so that you are not storing newsletters multiple times? I guess an example would be if say the newsletter changed their name or something?

@nak6608 Жыл бұрын

Great video was very helpful. However, in 4NF, the relation with Cust ID and Newsletter, shouldn't the Cust_ID be a foreign key not a primary key? It can't be a primary key because wilson44 shows up in multiple rows.