Urban75 Home About Offline BrixtonBuzz Contact

Trying to explain 2nd/3rd normal form

Man I am struggling to try and articulate the difference between 2nd and 3rd normal form to my BTEC lvl 3 students.

1st normal form is dead simple but while I can get the point across about attributes dependance on the primary key I'm getting stuck on the difference between 2 and 3.

It's probably mainly because I only just sorta get it myself but man I'm just coming up short on a way to put a simple explanation together for a bunch of bored 17 year old who are doing databases because they dropped out of the programming class.

Online resources aren't helping so far.
 

Pickman's model

every man and every woman is a star
Man I am struggling to try and articulate the difference between 2nd and 3rd normal form to my BTEC lvl 3 students.

1st normal form is dead simple but while I can get the point across about attributes dependance on the primary key I'm getting stuck on the difference between 2 and 3.

It's probably mainly because I only just sorta get it myself but man I'm just coming up short on a way to put a simple explanation together for a bunch of bored 17 year old who are doing databases because they dropped out of the programming class.

Online resources aren't helping so far.
does this help? Database Normalization: First, Second, and Third Normal Forms - Andrew Rollins

maybe this? Differences between 1st, 2nd and 3rd normal form | Business Intelligence Solutions Freelance Australia NSW Sydney
 
Not quite.

I find the process easier to do than to explain.

Those sites help somewhat but I'm still a long way from a nice set of rules written in a simple language to give to struggling students.
 
Well it's helping me with my understanding so that's a plus.

This unit is a wierd one. Doing some in depth stuff in theory but then setting criteria that force me to use access.
 

mauvais

change has become unavoidable
I might be oversimplifying this as databases are not my area of expertise, but:

2NF means you have to separate out data where its value can be inferred from part of the primary key.

3NF means you also have to separate out data that can be inferred from any other column.

Look at the 'green tick' answer here:

What are 1NF, 2NF and 3NF in database design?
 
Top