relation

A relation or relational attribute is an Attribute containing as values the ordinal number of the elements of another domain. It thereby defines a mapping from each element of the domain for which it is an attribute to that other Domain unit. The following picture illustrates this:

A relation has the source domain as domain unit and the related/target domain as Values unit. It’s a mapping from the source towards the related/target domain.

Synonyms in use for relation: Partitioning, Index attribute, relational attribute.

naming convention

It is advised to use the postfix _rel when naming index attributes, see also Naming conventions.

how to make

Relations are often made with a Rlookup or Point_in_polygon function. See also Relational attribute example.

use

Relations are often used in Relational functions and Aggregation functions.