What is and why do we need data modeling?
Data does not exist in a vacuum. Pure data without any surrounding knowledge rarely has any value. Data has a lot of value when you can put it into context and transform it into information.
Understanding data
The pure number 1.75, as you find it in a column of a database, by itself does not say much.
What do you think it represents?
It could be 1.75 meters, kilograms, gallons, seconds, or whatever unit you want to attach to it.
If instead of the pure number 1.75, you have 1.75 meters or 1.75 seconds, you already understand it much better, but you can’t really say that you know what this data is about yet.
If you have 1.75 meters in a column called width, then you know a bit more, but good luck guessing what that number really represents. If you also know it is in a table called car, product, or road, you can probably understand much better what it really represents.
By following through this very simple example...
