Derived attributes are not typically stored in a separate database table in a relational database model. Derived attributes are computed or derived from other attributes in the database. They are not stored directly in the database but can be calculated or derived when needed using queries or functions.
Derived attributes are derived based on the values of other attributes or data in the database. They can be calculated dynamically when a query or operation is executed, rather than being stored as persistent data in a separate table.
For example, if you have a database table with attributes like "height" and "weight," you can calculate the BMI (Body Mass Index) as a derived attribute based on the formula: BMI = weight / (height * height). The BMI value is not stored as a separate attribute in the table but can be computed on-the-fly when needed using a query or calculation.
So, in summary, derived attributes are not stored in a special database table but can be calculated or derived from other attributes during query execution or through functions and expressions.