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XML Schema selector Element


XML Schema Reference Complete XML Schema Reference

Definition and Usage

The selector element specifies an XPath expression that selects a set of elements for an identity constraint (unique, key, and keyref elements).

Element Information

  • Parent elements: key, keyref, unique

Syntax

<selector
id=ID
xpath=a subset of XPath expression
any attributes
>
(annotation?)
</selector>

(The ? sign declares that the element can occur zero or one time inside the selector element)

Attribute Description
id Optional. Specifies a unique ID for the element
xpath Required. Specifies an XPath expression, relative to the element being declared, that identifies the child elements to which the identity constraint applies
any attributes Optional. Specifies any other attributes with non-schema namespace


XML Schema Reference Complete XML Schema Reference


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