Sybase 7.5 manual Association role properties, Ordering, 101, Indicates

Models: 7.5

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Chapter 2 Building an Object-Oriented Model

Association role properties

You can define the following properties for each of the two roles of an association:

Multiplicity

Ordering

Visibility

Multiplicity

The cardinality of each of the two roles of an association is called the multiplicity. The multiplicity indicates the maximum and minimum number of values each role can have.

Cardinality

0..0

0..1

0..*

1..1

1..*

*

Number of instances

None

None or one

None to infinity

One to one

One to infinity

Infinity

Ordering

You can define the ends of an association as being ordered or sorted.

Property

Sorted

Ordered

Unordered

Indicates

That the set of objects at the end of an association are arranged according to the way they are defined in the model

That the set of objects at the end of an association are arranged according to in a specific order

That the end of the association is neither sorted nor ordered

101

Page 111
Image 111
Sybase 7.5 manual Association role properties, Ordering, 101, Indicates