DATA - Data Architecture > Data and Database Design > Synchronizing logical and physical models > "Logical to Physical" Synchronization Rules > Logical to Physical Synchronization: the Parts (UML)
Logical to Physical Synchronization: the Parts (UML)
Synchronization of parts is available by default with the new UML formalism. See Logical Data Modeling Options.
The result of the synchronization is determined by the combination of the Whole/Part link (None, Aggregation, Composition) and the Multiplicity defined on the part.
For more information on parts, see The Parts.
 
Multiplicity
Whole/Part link
Aggregation
Composition
None
 
None (*)
2 / 6
1..*
The part gives rise to a foreign key to the owner class
The part gives rise to a table between the two classes
1
0 / 1
The part gives rise to a foreign key to the referenced class
and gives rise to a foreign key to the owner class
 
 
The part gives rise to a foreign key to the referenced class
 
 
Example 1: None / * 
In the following example, the “Person” class references the “Car” class, without multiplicity constraint.
After synchronization, the “Car” part gives rise to a table:
• A column is created for each attribute of connected entities identifiers.
• The primary key for the table uses all these columns.
• A foreign key is also built for each connected entity.
Example 2: Aggregation / * 
A car can have one or several wheels.
After synchronization, the part gives rise to a foreign key to the “Car” class.
Example 3: Composition / 0..1 
An order contains an invoice.
After synchronization:
• A foreign key references the “Invoice” table in the “Order” table.
• A foreign key references the “Order” table in the “Invoice” table.