Database Keys Made Easy - Primary, Foreign, Candidate, Surrogate, & Many More 

Come on man!! Please do more videos. 😢

Same, what is it about universities and refusing to actually explain things in a relatable way? 😅

​@@joshualee7002 question of the century

@@joshualee7002 Idk if it's the same everywhere, but in the US they already have your money what do they care if you don't understand the classes?

Common University L

They really are

100% agree. The content, pace, diagrams and examples are extremely well thought out and presented. Adding one subscriber now!

I just increased the subscriber count.

​@@rudiklein Me too!

Because its not Indian English

Really glad I could help.

we need this

Same bro

Thanks! Yep, the idea was to make the explanations as easy and accessible as possible for people. Glad the video helped you.

Much appreciated! A video on joins is a good idea, I might create one of those at some point.

Working on it!

That is great to hear - I'm pleased that these tutorials have helped you so much.

Thanks! Actually my background is in business / systems analysis, translating user requirements into solutions. Just purely by chance, I got assigned to a lot of "data" projects and ended up specializing, without ever really intending to, in data modelling and in writing extract/transform/load (ETL) functional specs - especially in the context of data warehouses. There's a side of me that's very logical and precise and also very focused on communicating meanings clearly, all of which maybe accounts for why I find database design to be an interesting pursuit (& also why I like the challenge of finding ways to explain the concepts to others!)

Glad you liked the video! There are different schools of thought on this, but in my opinion you should try to use natural keys where possible ... the only problem is that it's very often not possible! So in practice, you'll find yourself using surrogate keys quite a lot of the time. A good example of a situation where you probably can and should use a natural key is in representing currencies (US Dollars, British Pounds, etc.) as these have official ISO Currency Codes (USD, GBP, etc.) Cases like this where there's a consensus standard natural key convention that you'll always be able to rely on are not that common, but when you do come across such a case, you should go for the natural key - that's my view, anyway. There are also times where you yourself are designing the whole system, including the front end, and can invent your own convention regarding codes to be displayed to the user that will represent instances a particular type of thing - like let's say 'O' for 'Open' and 'C' for closed. These are natural keys and it's fine and good to use them.

@@decomplexify Thanks for your feedback. What about in terms of speed. If you used ISO currency codes as a primary key, and then had to share that across multiple tables, would it have an impact on speed (and memory, as it might use more memory), as opposed to a primary key with just int's? What is your take on that?

@@danieldinnie5003 No, it wouldn't make a noticeable difference in modern database technology.

Glad you've been enjoying the videos! Much of the video is based on information that's available from a variety of different sources so it's not always easy to attribute the info to any particular book or books. Having said that, a couple of books by Chris Date that I was flipping through around the time I made the video are "Database Dreaming Volume II: Relational Writings Revised and Revived" and "Database in Depth".

Good suggestion - have enabled it now!