|
XPath 2.0
XPath 2.0 is a version of the XPath language defined by the World Wide Web Consortium, W3C. It became a recommendation on 23 January 2007. As a W3C Recommendation it was superseded by XPath 3.0 on 10 April 2014. XPath is used primarily for selecting parts of an XML document. For this purpose the XML document is modelled as a tree of nodes. XPath allows nodes to be selected by means of a hierarchic navigation path through the document tree. The language is significantly larger than its predecessor, XPath 1.0, and some of the basic concepts such as the data model and type system have changed. The two language versions are therefore described in separate articles. XPath 2.0 is used as a sublanguage of XSLT 2.0, and it is also a subset of XQuery 1.0. All three languages share the same data model (the XDM), type system, and function library, and were developed together and published on the same day. Data model Every value in XPath 2.0 is a ''sequence'' of ''items''. The items m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XPath
XPath (XML Path Language) is an expression language designed to support the query or transformation of XML documents. It was defined by the World Wide Web Consortium (W3C) and can be used to compute values (e.g., strings, numbers, or Boolean values) from the content of an XML document. Support for XPath exists in applications that support XML, such as web browsers, and many programming languages. Overview The XPath language is based on a tree representation of the XML document, and provides the ability to navigate around the tree, selecting nodes by a variety of criteria. In popular use (though not in the official specification), an XPath expression is often referred to simply as "an XPath". Originally motivated by a desire to provide a common syntax and behavior model between XPointer and XSLT, subsets of the XPath query language are used in other W3C specifications such as XML Schema, XForms and the Internationalization Tag Set (ITS). XPath has been adopted by a number of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World Wide Web Consortium
The World Wide Web Consortium (W3C) is the main international standards organization for the World Wide Web. Founded in 1994 and led by Tim Berners-Lee, the consortium is made up of member organizations that maintain full-time staff working together in the development of standards for the World Wide Web. , W3C had 459 members. W3C also engages in education and outreach, develops software and serves as an open forum for discussion about the Web. History The World Wide Web Consortium (W3C) was founded in 1994 by Tim Berners-Lee after he left the European Organization for Nuclear Research (CERN) in October 1994. It was founded at the Massachusetts Institute of Technology (MIT) Laboratory for Computer Science with support from the European Commission, and the Defense Advanced Research Projects Agency, which had pioneered the ARPANET, one of the predecessors to the Internet. It was located in Technology Square until 2004, when it moved, with the MIT Computer Science and Artificial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XPath 3
XPath 3 is the latest version of the XML Path Language, a query language for selecting nodes in XML documents. It supersedes XPath 1.0 and XPath 2.0. XPath 3.0 became a W3C Recommendation on 8 April 2014, while XPath 3.1 became a W3C Recommendation on 21 March 2017. New features in XPath 3.0 Compared to XPath 2.0, XPath 3.0 adds the following new features: ; Inline function expressions : Anonymous functions can be created in an expression context. For example, the expression creates a function that returns the product of its two arguments. The expression creates a sequence of functions, each one returning a different node from a collection. ; Dynamic function calls : Function values may be called without being referenced by name. For example, fetches the second item from sequence $f, and invokes it as a function, passing the string "Hi there" as argument. ; Union types : Union types, as defined in XML Schema, may be used in type conversions and function type signatures. ; Na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XPath 1
XPath (XML Path Language) is an expression language designed to support the query or transformation of XML documents. It was defined by the World Wide Web Consortium (W3C) and can be used to compute values (e.g., strings, numbers, or Boolean values) from the content of an XML document. Support for XPath exists in applications that support XML, such as web browsers, and many programming languages. Overview The XPath language is based on a tree representation of the XML document, and provides the ability to navigate around the tree, selecting nodes by a variety of criteria. In popular use (though not in the official specification), an XPath expression is often referred to simply as "an XPath". Originally motivated by a desire to provide a common syntax and behavior model between XPointer and XSLT, subsets of the XPath query language are used in other W3C specifications such as XML Schema, XForms and the Internationalization Tag Set (ITS). XPath has been adopted by a number of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XSLT 2
XSLT (Extensible Stylesheet Language Transformations) is a language originally designed for transforming XML documents into other XML documents, or other formats such as HTML for web pages, plain text or XSL Formatting Objects, which may subsequently be converted to other formats, such as PDF, PostScript and PNG. Support for JSON and plain-text transformation was added in later updates to the XSLT 1.0 specification. As of August 2022, the most recent stable version of the language is XSLT 3.0, which achieved Recommendation status in June 2017. XSLT 3.0 implementations support Java, .NET, C/C++, Python, PHP and NodeJS. An XSLT 3.0 Javascript library can also be hosted within the Web Browser. Modern web browsers also include native support for XSLT 1.0. For an XSLT document transformation, the original document is not changed; rather, a new document is created based on the content of an existing one. Typically, input documents are XML files, but anything from which the processor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XQuery
XQuery (XML Query) is a query and functional programming language that queries and transforms collections of structured and unstructured data, usually in the form of XML, text and with vendor-specific extensions for other data formats (JSON, binary, etc.). The language is developed by the XML Query working group of the W3C. The work is closely coordinated with the development of XSLT by the XSL Working Group; the two groups share responsibility for XPath, which is a subset of XQuery. XQuery 1.0 became a W3C Recommendation on January 23, 2007. XQuery 3.0 became a W3C Recommendation on April 8, 2014. XQuery 3.1 became a W3C Recommendation on March 21, 2017. Features XQuery is a functional, side effect-free, expression-oriented programming language with a simple type system, summed up by Kilpeläinen: XQuery provides the means to extract and manipulate data from XML documents or any data source that can be viewed as XML, such as relational databases or office documents. XQ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XQuery And XPath Data Model
The XQuery and XPath Data Model (XDM) is the data model shared by the XPath 2.0, XSLT 2.0, XQuery, and XForms programming languages. It is defined in a W3C recommendation.Anders Berglund, ''et al.''XQuery 1.0 and XPath 2.0 Data Model W3C, 2010, revised, 2015, Originally, it was based on the XPath 1.0 data model which in turn is based on the XML Information Set. The XDM consists of flat sequences of zero or more ''items'' which can be typed or untyped, and are either atomic values or XML Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable ... nodes (of seven kinds: document, element, attribute, text, namespace, processing instruction, and comment). Instances of the XDM can optionally be XML schema-validated. References {{Reflist External links * IBMXQuery and XPath data model Data ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XML Schema (W3C)
XSD (XML Schema Definition), a recommendation of the World Wide Web Consortium (W3C), specifies how to formally describe the elements in an Extensible Markup Language (XML) document. It can be used by programmers to verify each piece of item content in a document, to assure it adheres to the description of the element it is placed in. Like all XML schema languages, XSD can be used to express a set of rules to which an XML document must conform to be considered "valid" according to that schema. However, unlike most other schema languages, XSD was also designed with the intent that determination of a document's validity would produce a collection of information adhering to specific data types. Such a post-validation ''infoset'' can be useful in the development of XML document processing software. History XML Schema, published as a W3C recommendation in May 2001, is one of several XML schema languages. It was the first separate schema language for XML to achieve Recommendation stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XQuery And XPath Data Model Type Hierarchy
XQuery (XML Query) is a query and functional programming language that queries and transforms collections of structured and unstructured data, usually in the form of XML, text and with vendor-specific extensions for other data formats (JSON, binary, etc.). The language is developed by the XML Query working group of the W3C. The work is closely coordinated with the development of XSLT by the XSL Working Group; the two groups share responsibility for XPath, which is a subset of XQuery. XQuery 1.0 became a W3C Recommendation on January 23, 2007. XQuery 3.0 became a W3C Recommendation on April 8, 2014. XQuery 3.1 became a W3C Recommendation on March 21, 2017. Features XQuery is a functional, side effect-free, expression-oriented programming language with a simple type system, summed up by Kilpeläinen: XQuery provides the means to extract and manipulate data from XML documents or any data source that can be viewed as XML, such as relational databases or office documents. XQ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strong Typing
In computer programming, one of the many ways that programming languages are colloquially classified is whether the language's type system makes it strongly typed or weakly typed (loosely typed). However, there is no precise technical definition of what the terms mean and different authors disagree about the implied meaning of the terms and the relative rankings of the "strength" of the type systems of mainstream programming languages. For this reason, writers who wish to write unambiguously about type systems often eschew the terms "strong typing" and "weak typing" in favor of specific expressions such as "type safety". Generally, a strongly typed language has stricter typing rules at compile time, which implies that errors and exceptions are more likely to happen during compilation. Most of these rules affect variable assignment, function return values, procedure arguments and function calling. Dynamically typed languages (where type checking happens at run time) can also be stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weak Typing
In computer programming, one of the many ways that programming languages are colloquially classified is whether the language's type system makes it strongly typed or weakly typed (loosely typed). However, there is no precise technical definition of what the terms mean and different authors disagree about the implied meaning of the terms and the relative rankings of the "strength" of the type systems of mainstream programming languages. For this reason, writers who wish to write unambiguously about type systems often eschew the terms "strong typing" and "weak typing" in favor of specific expressions such as "type safety". Generally, a strongly typed language has stricter typing rules at compile time, which implies that errors and exceptions are more likely to happen during compilation. Most of these rules affect variable assignment, function return values, procedure arguments and function calling. Dynamically typed languages (where type checking happens at run time) can also be stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FLWOR
The programming language XQuery defines FLWOR (pronounced 'flower') as an expression that supports iteration and binding of variables to intermediate results. FLWOR is an acronym: FOR, LET, WHERE, ORDER BY, RETURN. FLWOR is loosely analogous to SQL's SELECT-FROM-WHERE and can be used to provide join-like functionality to XML Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. T ... documents. *''for'' creates a sequence of nodes *''let'' binds a sequence to a variable *''where'' filters the nodes on a boolean expression *''order by'' sorts the nodes *''return'' gets evaluated once for every node Example for $d in doc("depts.xml")//deptno let $e := doc("emps.xml")//employee eptno = $d where count($e) >= 10 order by avg($e/salary) descending return ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
