User manual

Defining identity constraints
68 PowerDesigner
For example:
Generated schema:
The KEYREF_UNIGOLD keyRef, defined on the product element, by
reference to the UNIGOLD unique constraint, specifies that the gold attribute
must be unique or null within the component_2 element, as well as it must be
unique or null within the component_1 element (See UNIGOLD).
To display a keyRef property sheet, double-click its name or its icon in the
Browser tree view.