# Logical Data Modeling - Domain (Permitted value set)

### Table of Contents

## About

A domain is a set of permitted, legal values of the same data type that a attribute can legitimately take on.

The set of values permitted is defined by:

- an enumeration,
- a range,
- or a format patterns (for string) (regular expression pattern)

A data type defines also a domain. Example: an integer defines the integer domain but a domain may be more restrictif such as the set of integer from 0 to 10.