relation - ObjectVision/GeoDMS GitHub Wiki
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 elated/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.