XML Schema unique Element
 Complete XML Schema Reference
Definition and Usage
The unique element defines that an element or an attribute value must be
unique within the scope.
The unique element MUST contain the following (in order):
- one and only one selector element (contains an XPath expression that
specifies the set of elements across which the values specified by field must
be unique)
- one or more field elements (contains an XPath expression that specifies
the values that must be unique for the set of elements specified by the
selector element)
Element Information
Syntax
<unique
id=ID
name=NCName
any attributes
>
(annotation?,(selector,field+))
</unique>
|
(The ? sign declares that the element can occur zero or one time
inside the unique element)
| Attribute |
Description |
| id |
Optional. Specifies a unique ID for the element |
| name |
Required. Specifies a name for the element |
| any attributes |
Optional. Specifies any other attributes with non-schema
namespace |
Complete XML Schema Reference
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