NORMA Lab 2
shows an ORM schema that illustrates most aspects of the ORM graphical notation discussed in this chapter. This diagram was drawn using the ORM2 stencil for Microsoft Visio, but for this lab we’ll see how to enter this schema in the NORMA tool.
Note the shadows around the Sport and Rank object type shapes. These indicate that the shape appears multiple times in the diagram. The ability to duplicate shapes on a diagram is useful for avoiding line crossings. Although line crossings are allowed, they tend to make the diagram appear cluttered, so are best avoided for aesthetic reasons.
Figure 2.26 A Visio diagram of the ORM ...