Adding an identifier attribute to the newly created class

Promoting the multivalued attribute to a class of objects

Always replacing the multivalued attribute with a one-to-many association

Removing the multivalued attribute from the original class

Reification method

Superset method

Association method

Subset method

Superset method

Association method

Subset method

Inheritance chain method

The new class must have a single-attribute identifier

The new class receives a composite identifier contributed by both sides

The new class receives identifiers from only one side

The new class replaces both associated classes

(bldg#, room#)

room#

bldg#

Either bldg# or room#

Only identifiers are retained, all other attributes removed

Only PK-tagged attributes appear

CK-tagged attributes are removed

FK-tagged attributes become foreign keys referencing other schemas

An attribute belongs to an entity

The relationship is 1:1 only

The attribute is composite

An attribute depends on a relationship occurrence between two objects

Company involved in Building (derivable from Company–Stage and Stage–Building)

Research paper written by Author

Company involved in Construction Stage

Employee supervises Employee

Largest numeric range

Minimum attribute count and minimal chance of value change

Contains descriptive attributes

Strongest semantic meaning

Constraints

SQL CREATE TABLE

Verbs

Nouns and noun phrases