Adding a TreeSet Collection to a TreeSet Definition
At creation a TreeSet Definition includes a single TreeSet Collection: the root TreeSet Collection. You may need to add one or several TreeSet Collections to the TreeSet Definition structure.
To add a TreeSet Collection you must define:
• where you want to add the TreeSet Collection in the TreeSet Definition structure
• how you want to populate the TreeSet Collection:
• a parameter
• a MetaAssociationEnd
• a query
Adding a TreeSet Collection populated by a MetaAssociationEnd
To add a TreeSet Collection populated by a MetaAssociationEnd:
1. Access the TreeSet Definition properties.
2. Display its Definition page.
3. In the TreeSet Definition, right-click the TreeSet Collection (or the root) under which you want to add a TreeSet Collection, and select New > TreeSet Collection.
4. Enter a Local name to the TreeSet Collection.
5. In the Collection is populated by drop-down list, keep "MetaAssociationEnd".
6. In the Populating MetaAssociationEnd drop-down list, select the MetaAssociationEnd.
The list includes available MetaAssociationEnds only, i.e. the MetaAssociationEnds of the parent TreeSet Collection.7. Click OK.
The TreeSet Collection is added to the TreeSet Definition under the parent TreeSet Collection.
8. (If needed) Define the TreeSet Collection.
Adding a TreeSet Collection populated by a query
You can use a provided query or create your own query.
To add a TreeSet Collection populated by a query:
1. Access the TreeSet Definition properties.
2. Display its Definition page.
3. In the TreeSet Definition, right-click the TreeSet Collection (or the root) under which you want to add a TreeSet Collection, and select New > TreeSet Collection.
4. Enter a Local name to the TreeSet Collection.
5. In the Collection is populated by drop-down list, select "Query".
The Populating Query field is displayed and includes the list of available queries only, i.e. the queries related to the parent TreeSet Collection.
6. In the Populating Query drop-down list, select the query.
Else click the right-oriented arrow to create a query.7. Click OK.
The TreeSet Collection is added to the TreeSet Definition under the parent TreeSet Collection.
8. (If needed) Define the TreeSet Collection.
Adding a TreeSet Collection populated by a parameter
To add a TreeSet Collection populated by a parameter:
1. Access the TreeSet Definition properties.
2. Display its Definition page.
3. In the TreeSet Definition, right-click the TreeSet Collection (or the root) under which you want to add a TreeSet Collection, and select New > TreeSet Collection.
4. Enter a Local name to the TreeSet Collection.
5. In the Collection is populated by drop-down list, select "Parameter".
The Populating Parameter field is displayed and includes the list of available parameters only, i.e. the parameters related to the parent TreeSet Collection.
6. In the Populating Parameter drop-down list, select the parameter (which is a Collection Parameter).
7. Click OK.
The TreeSet Collection is added to the TreeSet Definition under the parent TreeSet Collection.
8. (If needed) Define the TreeSet Collection.
Removing a TreeSet Collection from a TreeSet Definition
When you remove a TreeSet Collection from a TreeSet Definition, you also remove all its child TreeSet Collections and TreeSet Properties.
You can choose to remove the TreeSet Collection from the TreeSet Definition only or delete it from HOPEX repository.
To remove a TreeSet Collection from a TreeSet Definition:
1. Access the TreeSet Definition folders.
2. Expand the TreeSet Definition concerned.
3. Right-click the TreeSet Collection you want to remove from the TreeSet Definition and select Remove 
.
.A confirmation dialog box prompts you to confirm your choice to remove the TreeSet Collection from its TreeSet Collection parent only or delete it from HOPEX repository.
if you want to delete the TreeSet Collection from the HOPEX repository, select Delete and confirm your choice in the next window.4. Click Remove.
The TreeSet Collection is removed from the TreeSet Definition, but still available in the HOPEX repository.