Displaying Referential Integrity and Cardinality on a Reference Symbol

To set display preferences for references, select Tools > Display Preferences , and select the Reference sub-category in the left-hand Category pane.

Referential Integrity

The notation for referential integrity on reference symbols is as follows:

upd() - Update
del() - Delete
cpa - Change Parent Allowed

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

( ) - None
(R) - Restrict
(C) - Cascade
(N) - Set null
(D) - Set default

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).

Cardinality

Select the Cardinality attribute to display the minimum and maximum number of instances in a child table that can appear for each corresponding instance in the parent table.

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.

Reference Display Mode

For information about changing the notation of references, see Setting Model Settings. For general information about PDM display preferences, see "Display Preferences" in the Core Features Guide.

Note:

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.