Data Modeling - (Derived|Calculated) Attribute (Derived Data)

> (Data|State) Management and Processing > Data Modeling (RDBMS or Code)

1 - About

Derived is a property of:

The value can be calculated or deduced from relationship Groupings or from the values of other variable. The value of a Derived variable changes constantly.

There is then a functional dependency between two variables.

Use Explicit data instead of derived data Jing Chen - Facebook - Hacker Way: Rethinking Web App Development at Facebook

Never focus just on the data in front of your eyes, or on derived variables, like percentages or rates Alberto Cairo - When doing data reporting, look at the raw numbers, not just at percentages —and write an accurate headline


3 - UI

This kind of dependency is really common in UI development when one action must refresh a part of the UI. It's often implemented with an observer pattern.

4 - Examples

  • Student Age,
  • Account Balance,
  • Number of courses taken.
data/modeling/derived.txt · Last modified: 2017/11/16 23:06 by gerardnico