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Creating a Relation Definition

 When you create a relation definition, you are creating an instance of the RELATION class. For a summary, see The Relation Class.

To create a relation definition:


  1. Select KB Workspace > New Definition > relation, and click to place the relation definition on the workspace.

  2. Display the relation definition's table, and edit the Relation-name attribute to specify the relation's name.

  3. Enter the relation source class in the First-class attribute.

  4. Enter the relation target class in the Second-class attribute.

When you create a relation based on its definition, you conclude that one or more items of the First-class are related to one or more items of the Second-class via the Relation-name. For more information, see Creating a Relation.

Choosing a Relation Name

When specifying the Relation-name attribute of a relation definition, choose a name that is descriptive and meaningful when read in a conclude action.

Unlike most items, a relation definition does not include a Names attribute. The name of a relation is the symbol you provide in the Relation-name attribute. For a description of how you use the conclude action with relations, see Creating a Relation.

For example, you might conclude that a particular tank is the-holding-tank-for another tank.

When concluding that a particular tank is one of many holding tanks for another tank, you might use the prefix a in the relation name:

Sometimes relation names refer to a location, for example, a bottle might be located-at a station:

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