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relates

The relates keyword is used in TypeQL schema to define a role of a relation type.

Syntax

The syntax of a relates statement includes:

  • Subject — type label of a relation type

  • Predicate — the relates keyword

  • Object — type label of a role

Syntax
<relation-type> relates <role> [as overridden-type];

An optional override can be added at the end.

Behavior

TypeQL statements with the relates keyword can be used only in Define and Undefine queries.

The relates keyword adds a new role to a relation type.

Usage in a schema definition

For this example, use a database with the IAM schema and sample data loaded.

Since in Define and Undefine queries you can’t use variables, both subject and object can only be type labels.

For example, to define a new role subject for the permission relation type, use:

Define role query example
define
permission relates subject;

To remove the new role, use:

Undefine query example
undefine
permission relates subject;

Usage with override

By default, a subtype of a relation type inherits all roles that were defined for its supertype. To override an inherited role, use the as keyword.

Let’s see an example, of a schema, where the owned role of the ownership relation type gets overridden by the object role:

Override owned attribute type example
define

object-ownership sub ownership,
    owns ownership-type,
    relates object as owned;

Learn more

Learn more about type statement in TypeQL.

Learn about types in TypeQL.

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