Difference between revisions of "Prov-XML Identifiers"

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(= Disadvantages)
(Contraints)
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==== Contraints ====
 
==== Contraints ====
  
'''Validity constraint: ID'''
+
: '''Validity constraint: ID'''
  
Values of type ID must match the Name production. A name must not appear more than once in an XML document as a value of this type; i.e., ID values must uniquely identify the elements which bear them.
+
: Values of type ID must match the Name production. A name must not appear more than once in an XML document as a value of this type; i.e., ID values must uniquely identify the elements which bear them.
  
'''Validity constraint: One ID per Element Type'''
+
: '''Validity constraint: One ID per Element Type'''
  
No element type may have more than one ID attribute specified.
+
: No element type may have more than one ID attribute specified.
  
'''Validity constraint: ID Attribute Default'''
+
: '''Validity constraint: ID Attribute Default'''
  
An ID attribute must have a declared default of #IMPLIED or #REQUIRED.
+
: An ID attribute must have a declared default of #IMPLIED or #REQUIRED.
  
'''Validity constraint: IDREF'''
+
: '''Validity constraint: IDREF'''
  
Values of type IDREF must match the Name production, and values of type IDREFS must match Names; each Name must match the value of an ID attribute on some element in the XML document; i.e. IDREF values must match the value of some ID attribute.
+
: Values of type IDREF must match the Name production, and values of type IDREFS must match Names; each Name must match the value of an ID attribute on some element in the XML document; i.e. IDREF values must match the value of some ID attribute.
  
 
==== Advantages ====
 
==== Advantages ====

Revision as of 18:59, 17 January 2013

Discussions on how to represent identifiers (prov:id) in PROV-XML

Options regarding the type of the prov:id and prov:ref xml attributes

Using xs:ID for prov:id and xs:IDRef for prov:ref

Contraints

Validity constraint: ID
Values of type ID must match the Name production. A name must not appear more than once in an XML document as a value of this type; i.e., ID values must uniquely identify the elements which bear them.
Validity constraint: One ID per Element Type
No element type may have more than one ID attribute specified.
Validity constraint: ID Attribute Default
An ID attribute must have a declared default of #IMPLIED or #REQUIRED.
Validity constraint: IDREF
Values of type IDREF must match the Name production, and values of type IDREFS must match Names; each Name must match the value of an ID attribute on some element in the XML document; i.e. IDREF values must match the value of some ID attribute.

Advantages

  1. xs:ID recognized by XML tools as an identifier type
  2. xs:IDRef recognized by XML tools as a reference to an identified element

Disadvantages

  1. ID and IDRef have a base type of NCName
    1. cannot contain colons, whitespaces, or start with numbers
    2. URIs and qualified names are not valid IDs because both contain colons.

xs:QName/xs:QName

xs:anyURI/xs:anyURI