Malo sam trazio. A <xs:keyref>??? Kako ovde pise potpuno je podrzan od strane XSD-a i potpuno ekvivalentan tagu <msdata:Relationship>...
The XSD keyref Element
In XSD, the keyref element allows you to establish links between elements within a document in much the same way a parent/child relationship does. The WriteXml method uses keyref to express a relation within a DataSet object, as shown here:
<xs:keyref name="Emp2Terr" refer="Constraint1">
<xs:selector xpath=".//Territories" />
<xs:field xpath="@employeeid" />
</xs:keyref>
The name attribute is set to the name of the DataRelation object. By design, the refer attribute points to the name of a key or unique element defined in the same schema. For a DataRelation object, refer points to an automatically generated unique element that represents the parent table, as shown in the following code. The child table of a DataRelation object, on the other hand, is represented by the contents of the keyref element.
<xs:unique name="Constraint1">
<xs:selector xpath=".//Employees" />
<xs:field xpath="employeeid" />
</xs:unique>
The keyref element’s contents consist of two mandatory subelements—selector and field—both of which contain an XPath expression. The selector subelement specifies the node-set across which the values selected by the expression in field must be unique. Put more simply, selector denotes the parent or the child table, and field indicates the parent or the child column. The final XML representation of our sample DataRelation object is shown here:
<xs:unique name="Constraint1">
<xs:selector xpath=".//Employees" />
<xs:field xpath="employeeid" />
</xs:unique>
<xs:keyref name="Emp2Terr" refer="Constraint1">
<xs:selector xpath=".//Territories" />
<xs:field xpath="@employeeid" />
</xs:keyref>
This code is functionally equivalent to the msdata:Relationship annotation, but it is completely expressed using the XSD syntax.
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