Cardinality (source cardinality)
Attribute: Specifies the number of connections (capability) between the source object and the target object.
1 (
) = One unit (1)
c (
) = None or one unit (0 and 1)
cn (
) = None to any number of units (0 to infinite)
n (
) = One to any number of units (1 to infinite)
2... (
) = Two and more units (2 to infinite)