Unique Checks

PowerDesigner provides default model checks to verify the validity of uniques.

Check	Description and Correction
Unique name and code uniqueness	Unique constraint names and codes must be unique in the model. Manual correction: Modify the duplicate name/code. Automatic correction: Appends a number to the duplicate name/code.
Existence of fields	A unique constraint must contain at least one field. Manual correction: Add at least one field to the unique constraint or delete the unique constraint. For example: @numEmployee. Automatic correction: Deletes unassigned unique constraint. For more information on fields, see Specifying Constraint Fields.
Undefined Selector	You must define an XPath expression for a unique constraint selector attribute. Manual correction: In the unique constraint property sheet, define an XPath expression for the unique constraint selector attribute. For example: s:company/s:employee. Automatic correction: None For more information on XPath expressions, see Specifying a Constraint Selector.

Check

Description and Correction

Unique name and code uniqueness

Unique constraint names and codes must be unique in the model.

Manual correction: Modify the duplicate name/code.

Automatic correction: Appends a number to the duplicate name/code.

Existence of fields

A unique constraint must contain at least one field.

Manual correction: Add at least one field to the unique constraint or delete the unique constraint. For example: @numEmployee.

Automatic correction: Deletes unassigned unique constraint.

For more information on fields, see Specifying Constraint Fields.

Undefined Selector

You must define an XPath expression for a unique constraint selector attribute.

Manual correction: In the unique constraint property sheet, define an XPath expression for the unique constraint selector attribute. For example: s:company/s:employee.

Automatic correction: None

For more information on XPath expressions, see Specifying a Constraint Selector.