You can rename a relationship if you want to abbreviate the system-assigned relationship name, or if you want to replace it with a user-defined name. When you rename a relationship, the relationship name is automatically updated in the current diagram and any other diagram in which it appears.
To rename a relationship
The relationship is renamed in the diagram and any other diagram in which it appears as soon as you exit the Relationship name box; it is renamed in the database when you save either of the related tables or the diagram.
Tip If you want to see labels for relationship lines, use the Show Relationship Labels command. For more information on relationship labels and this command, see Adding Labels to Relationship Lines.