Modifying multiplicity


Multiplicity is the specification of the range of allowable cardinality that a set can assume. Multiplicity specifications can be given to roles within associations, parts with composites, repetitions and other purposes. Essentially, a multiplicity is a (possible infinite) subset of the positive integers.

When an association is created, default multiplicities 0,N and 1,1 are attributed to the source and target tables respectively. However, it is possible to change the multiplicity factor in the association.
  1. Place the pointer tool on the role (or association) descriptor label and right-click it.
  2. Select Multiplicity from the pop-up menu and then the desired cardinality.


You can also change an association’s multiplicity from the design panel. Left-click the role (or association) descriptor label and edit the multiplicity line.