Deleting

The Delete operation removes a relationship from the ontology. If a term has more than one parent, Delete removes one relationship at a time. If a term has only one parent, deleting the last relationship makes the term obsolete.

To delete one or more relationships, first select the relationship(s) to be deleted. Choose the "Delete relationship" option from the edit menu or right-click menu. You can use the Delete operation to delete more than one relationship at once: Delete affects all selected relationships, provided that they can all be deleted (see below for the exception).

When a term has only one parent, the menu item will say "Delete term (make obsolete)", and if you delete it, a warning will appear:

If you click "Yes" the term will become obsolete; if you click "No" no action is taken.

Note that if a term has children, it cannot be made obsolete; the children must be removed (moved or deleted) first. If you select a term that has one parent and one or more children, the Delete menu item will not be available (it will be greyed out). If you select more than one term, and one of the selected terms has one parent and one or more children, a warning will appear indicating that the term with children will not be deleted:

If you click "Yes" the terms without children will be deleted (and made obsolete if they have no other parents, as in the figure); if you click "No" no action is taken. In either case the term with children is not deleted.