Manipulating Relationship Collections

You cannot add or delete a relationship collection after it is created. A relationship collection might consist of zero relationships, but the collection still exists. If you retrieve such a relationship collection, the Repository returns an interface pointer to a relationship collection, just as it would return for any other relationship collection.

The following figure shows four projects; each project has a collection of relationships that associate it with its subprojects.

• Genome project — the collection has two relationships.
  
  
• Grant proposal 108 project — the collection has one relationship.
  
  
• General research project — the collection has zero relationships.