Previous Table of Contents Next


5.6.2 KeysIndexes Associations


   5.6.2.1 IndexedFeatureInfo Protected

   The IndexedFeatureInfo association connects an Index instance to information about how the StructuralFeature instances that are constituents of the Index’s key are used by the Index.

   Ends

   index indexedFeature

Identifies the Index instance for which this IndexedFeature instance is relevant.

class:

multiplicity:

Index
exactly one

Identifies the IndexedFeature instance that associates this Index with one of the StructuralFeature elements of the Index’s key. The ordered constraint on this reference can be used to represent the sequential order of elements of the Index’s key.

class:

multiplicity:

aggregation:

IndexedFeature
zero or more; ordered
composite

   5.6.2.2 IndexedFeatures

   The IndexedFeatures association links StructuralFeature instances to information about how they participate in the keys of Index instances.

   Ends

   feature

Identifies the StructuralFeature instance for which this IndexedFeature instance is relevant.

class:

multiplicity:

StructuralFeature
exactly one

   indexedFeature

Identifies the IndexedFeature instances that describe how a particular StructuralFeature is used by the keys of Index instances.

class:

multiplicity:

IndexedFeature
zero or more

   5.6.2.3 IndexSpansClass

   Associates indexes with the classes they span. This relationship is separate from the ownership of indexes, to allow modeling of systems where an index is NOT owned by the object it spans. In most situations, however, the spanned and owning Class instances will be the same.

   Ends

   index spannedClass

Identifies Index instances that span this Class instance.

class:

multiplicity:

Index
zero or more

Identifies the Class instance the Index instance spans.

class:

multiplicity:

Class
exactly one

   5.6.2.4 KeyRelationshipFeatures

   The KeyRelationshipFeatures association links KeyRelationship instances with the StructuralFeature instances that comprise their key.

   Ends

   feature

Identifies StructuralFeature instances that participate as (part of) the key of this KeyRelationship instance. In the relational case, this reference indicates the columns that make up the foreign key.

class:

multiplicity:

StructuralFeature
one or more; ordered

   keyRelationship

Identifies the KeyRelationship instances that employ a particular StructuralFeature as part of their key.

class:

multiplicity:

KeyRelationship
zero or more

   5.6.2.5 UniqueFeature

   The UniqueFeature association identifies the Feature instances of a Class instance that confer uniqueness. The ordered constraint is used to determine the order of StructuralFeature instances in the UniqueKey instance.

   Ends

   feature uniqueKey

Identifies the StructuralFeature instances that make up the unique key. The ordered constraint is used to represent the sequence of StructuralFeature instances that make up the UniqueKey instance’s key. In the relational model case, these StructuralFeature instances identify the columns that make up a table’s primary key.

class:

multiplicity:

StructuralFeature
one or more; ordered

Identifies the UniqueKey instances in which a particular StructuralFeature participates.

class:

multiplicity:

UniqueKey
zero or more

   5.6.2.6 UniqueKeyRelationship Protected

   The UniqueKeyRelationship association links a KeyRelationship with the UniqueKey with which it is paired. For example, in relational model terms, this association links a foreign key -- the KeyRelationship instance -- with the primary key -- the UniqueKey instance -- with which it is paired.

   Ends

   keyRelationship

Identifies the KeyRelationship instances with which a particular UniqueKey instance is paired.

class:

multiplicity:

KeyRelationship
zero or more

   uniqueKey

Identifies the KeyRelationship instances that reference this UniqueKey instance. In the relational case, this reference identifies the foreign keys that reference this primary key.

class:

multiplicity:

UniqueKey
exactly one