Modifying the reference display preferences

Chapter 3 Building Physical Diagrams

Modifying the reference display preferences

Reference text

You can modify the following display preferences for a reference:

Label	Displays
Name	Name or code of the reference*
Constraint name	Referential integrity constraint name
Join	Statement of linked columns between the two tables
Referential integrity	Update and delete referential integrity constraints.
Stereotype	Stereotype of the reference
Role names	Role names for parent and child tables of the reference
Cardinality	Minimum and maximum number of instances in a child table that can appear for each corresponding instance in the parent table
Implementation	Implementation mode of referential integrity, declarative or by triggers

*Displayed text depends on whether the Name or Code radio button is selected.

Reference display mode

You now set the display mode of reference symbols by selecting a global notation in the Model Options dialog box. Whereas in previous versions, it was possible to set a different notation per diagram in the same model using the reference display preferences now, when you open a model saved in a previous version, the reference notation in the default diagram is used to initialize the model notation.

PowerDesigner supports the Relational, CODASYL, Conceptual, and IDEF1X notations:

For information about changing the notation, see the section "Setting PDM Model Options".

Referential integrity label

The referential integrity label indicates update and delete integrity, as follows:

Label	Referential integrity
upd()	Update
del()	Delete
cpa	Change Parent Allowed

A letter between the parentheses indicates the type of constraint, as follows:

Label	Referential integrity
( )	None
(R)	Restrict
(C)	Cascade
(N)	Set null
(D)	Set default

Default Cardinality labels

The default cardinality labels for PowerDesigner indicate the minimum and maximum number of children as follows:

 [minimum..maximum]

For example, the cardinality label

[0..n]

indicates that any number of children is acceptable.

Referential integrity example

The referential integrity label shown below indicates the following:

Cascade on update
Set null on delete
Cardinality is
```
0..n
```
(any number of children is acceptable).

Moving text on a reference symbol
When a reference symbol displays text, the text position is based on the position of handles. You can add a handle on the reference symbol by pressing ctrl while you click the symbol.