Database Normalisation

The goals of normalising a database, along with a worked example.

I'm Mr. Woo and my channel is all about learning - I love doing it, and I love helping others to do it too. I guess that's why I became a teacher! I hope you get something out of these videos - I upload almost every weekday, so subscribe to find out when there's something new!

[namahshrestha]

Eddie Woo teaching DBMS..thank you Lord for this. Seriously, I have a strong feeling that all my doubts will be cleared.

[FunnyVideos-niiu]

Eddie, you Sir are the best teacher i've seen in ages! and probably will see in a long time! the way you teach radiates so much positive energy, so much enthusiasm, your teaching style is amazing it just pulls me into the subject and like magic you make everything easy! I bet you have the potential to build something like KhanAcademy and impacting millions all over the world. I can already see people loving your teaching style at EddieAcademy or whatever you wish to call your online teaching platform, YOU ARE A ROCKSTAR TEACHER!! Thank you so much for making complex subjects easy for us to understand and sharing it freely on YouTube. God Bless You with Super Success in your goals in life! You've earned a fan for life, liked and subbed

[manixpc]

Really exceptional job teaching! Kept me engaged throughout.

[francisantoniochikondejr]

i love your videos Mr Woo. so much energy in them and your teachings are very well clear.

[usmans]

Mr.Woo you have great teaching skills.

[soja]

I found the best teacher literally the
opposite side of the world!

[HappyLittleSoulGames]

Eddie, you are a champion!!  Exceptional job, I wish my lecturer was more like you - I actually understand what is going on now :) Thank you

[StephanWells]

This is really great and easy to understand. I have a databases exam tomorrow and I've been at a loss with the subject (and normalisation specifically) since my databases lecturer isn't very good at explaining coherently (nobody understands him!). His online notes are also near-impossible to understand due to how vague and full of mistakes they are. So yeah, for me this video is a lifesaver haha.

Only thing I'd ask for is, like the others said, a more distinct representation of the normalisation steps. You didn't really mention when one normal form stops and the next normal form starts. I don't know how important it is to be able to distinguish the three normal forms over there, but here in Malta, in exam questions they often ask things like "normalise this database to 2NF" or "is this database in 1NF?", etc.

Anyway, keep doing what you're doing! Thanks for the explanation.

[haka]

It's a good introduction into relational databases but it also gives students an illusion that relational split up is always the best solution.
In the real world it can be highly inefficient to go for a relational design and make maintenance a lot more time consuming.
Especially these days with big data flat tables are often the way to go, despite containing redundant data and looking less elegant.

[aszneemabrotha]

Studying IPT at NSBH this year for the HSC. Thanks so much for your videos!

[mattmiller]

This is an awesome video.  You're really good at presenting this material. 

Do you have any videos that go over what each normal form is?  Like, first normal form is when your DB is this, second normal form is this, so on and so fourth.

[kuchigyz]

Who else said "bless you" out loud while watching this?

[Hevletica]

I have an issue regarding the final form of the table. You mentioned at 3:46 "InvNum" being the primary key of the purchase table, however this can't be true due to one ID instance being repeated several times at the end of the video. Wouldn't it be more feasible to create a surrogate key instead?

[vilkoos]

The basic idea of databases/normalization is definitely not efficiency,
The basic ideas/goal are:
- to record each fact only once, avoid data redundancy above all else (this often introduces CPU-use "inefficiencies" )
- to make data-storage independent of the needs of the applications that use the data (again this causes "inefficiencies")

Normalization (i.e. putting the data in an standard form) is a technique that:
- assures that data redundancy is minimal
- creates a data structure that is only dependent on the logic of the data itself (it uses the logic of functional dependency)
the logic of the data structure is completely decoupled of the logic of the process that uses the data.

[yascel]

U are so helpful. I have my trials and this is so informative continue what your doing :)

[roelmangubat]

2014, and it still is a great video. Very helpful indeed.

[venkateshkannan]

Awesome tutorial. Thank you Mr.Woo. Do you have the spreadsheet used in this file on the site? I couldn't find it there.

[aks]

Great video. I understood the concept of normalization but you know I have this Normalization in my syllabus and the question goes something like this
Find 3NF decompostion of the relation schema
and then i am given with a set of tables with no values in it. what should i do?? put my own values there??

[krishan]

Dear sir, if you are aware of SOFTWARE TESTING, please upload some clips, thanks

[SKEptic-mgdd]

Wish I saw this before spending months trying to make MS Access work for me.