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Relationship

For the purposes of this guide, we refer to the concept of a similarity or connection between two spheres as a Relationship while, for a specific instance of a relationship, operating between two particular sphere items we use the term, Relation, which is categorised by its Relation Value.

To use the Relation Definition Manager, go to the Facilities page of the Main Menu and click the Customise Relationships button.

New Relationship

To define a new relationship, use Control with Page Up or Page Down to go to the from sphere of the pair. Then use Page Down to go to the to sphere of the pair. You can recognise existing relationships by the presence of at least one relation value. For a new relationship, entry of at least one relation value is the necessary and sufficient condition for generating a new relations table.

For each possible relation between the spheres there are three elements, the forward relation value (forward name), the inverse relation value (inverse name) and the relation code. (See spheres and relationships.) When you enter each relation name, note that the code is initially set to the first character of the forward name and the inverse name to the same value as the forward name. Relation codes are not used in the main processes or forms of Strategy SAVI® but can be used in generated matrices to minimise their size. If you inadvertently create a set of names with duplicate codes, you will be prompted to change one or both of them when you move to another relationship or leave the form.

Changing a Relationship

You can add new relation values to an existing relationship or even change existing values. If you change a value, a dialogue box will give you the alternatives of removing all recorded relations which currently use the relation value or changing them to the new value. Thus you can remove an unwanted value or change to a more appropriate term for a valid value. Old relation values may also be left in place for further consideration and individual update or removal if required.

Attribute Definition

To add or change relationship attributes, alter the appropriate names and set the types in the User Definable Relation Fields area. Undefined attributes default to a name of the form "Free Field n" with a type of "A1". (See attribute types.) From a methodological viewpoint, you can think of the representation as Chen-like with attributes of the relationship defined here.

Recursive Relationships

The first available relationship displayed for a sphere is the recursive relationship from the sphere to itself. Examples of the use of this include the "subtype" relationship used in data modelling where a sphere item (Data entity) "May be" one of several different types. A similar relation applies to object classes. See the note on recursive relationships for specific details.

Another possible use of the recursive relationship is to define process or other flows. These are further discussed in Creating a Flow Relationship.

Remove a Relationship

You can remove an unwanted sphere by clicking the Delete Rel'n button or by deleting all its Relation Names. When you move to another relationship or leave the form, the relation table will be deleted and the relation definition entry will revert to empty.

Relationship Definition Manager Form

Additional facilities on the form let you view or print a graphic representation of the whole schema, to print the Schema Report or to add a formatted text note to define the characteristics or meaning of the relationship.

Click to see the detail of the form.