A property of a set of values, such as the set of objects related to an object across an association, stating whether the set is ordered or unordered.
See also association, association end, multiplicity.
If the multiplicity upper bound on an attribute or association end is greater than one, then a set of objects is associated with the attribute slot or the end of an association. The ordering property declares whether the set is ordered or unordered. If it is unordered, the objects in the set have no explicit order; they form an ordinary set. If it is ordered, the elements in the set have an explicitly imposed order. The element order is part of the information represented by the association—that is, it is additional information ...