Defining elements

Element constraints properties

Identity constraints allow you to indicate that element values must be unique within their specified scope.

You can use the Constraints page of an element property sheet to add the following constraints to an element declaration:

Tool

Tooltip

Description

 

Key Constraint

The element value must be a key within the

 

 

specified scope. The scope of a key is the

 

 

containing element in an instance document. A

 

 

key must be unique, not null, and always

 

 

present

 

Unique Constraint

The element value must be unique or null

 

 

within the specified scope

 

KeyRef Constraint

The element value corresponds to those of the

 

 

specified key or unique constraint

 

 

 

You can access directly to the Constraints page of an element property sheet through the contextual menu. Right-click an element symbol in the diagram and select Constraints in the contextual menu.

For more information on constraints, see section Defining identity constraints.

Element mapping properties

 

Object mapping is the ability to establish a correspondence between objects

 

belonging to heterogeneous models and diagrams.

 

The Mapping page of an element property sheet allows you to map the

 

current element and its attributes to PDM or OOM objects.

 

Select a data source in the Mapping for dropdown listbox. If it is the first

 

time you define a mapping for an element, the Mapping for dropdown listbox

 

is empty. Click the Add a Mapping for a Data Source tool and select a data

 

source.

Element Sources

The Element Sources page allows you to associate one or several PDM or

page

OOM objects to the current element.

 

You can use the Add Objects tool to select objects from the PDMs or OOMs

 

opened in the current workspace.

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Sybase XML manual Element constraints properties, Element mapping properties, Element Sources