The term XML Updates refers to the act of modifying XML data while preserving its identity, through the operators provided by an XML manipulation language. Identity preservation is crucial to this definition: the production of XML data from XML data without preserving the original data identity is called XML transformation. The general notion of identity has many concrete incarnations. The XQuery/XPath data model (see [2]) associates a Node Identity to each node of the XML syntax tree. In a language based on this data model, updates differ from transformations because the former modify the data but preserve node identities. Another hallmark of updates is that an expression that refers to the data being updated may have a different value after the update is evaluated, while the evaluation of XML transformations does not change the value of any other expression.
XML Updates
Ghelli Giorgio
2017-01-01
Abstract
The term XML Updates refers to the act of modifying XML data while preserving its identity, through the operators provided by an XML manipulation language. Identity preservation is crucial to this definition: the production of XML data from XML data without preserving the original data identity is called XML transformation. The general notion of identity has many concrete incarnations. The XQuery/XPath data model (see [2]) associates a Node Identity to each node of the XML syntax tree. In a language based on this data model, updates differ from transformations because the former modify the data but preserve node identities. Another hallmark of updates is that an expression that refers to the data being updated may have a different value after the update is evaluated, while the evaluation of XML transformations does not change the value of any other expression.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
