# XQuery

> functional programming and query language for XML

**Wikidata**: [Q850661](https://www.wikidata.org/wiki/Q850661)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/XQuery)  
**Source**: https://4ort.xyz/entity/xquery

## Summary
XQuery is a functional programming and query language designed specifically for querying and manipulating XML data. It is a declarative language that combines functional programming principles with the ability to extract and transform data from XML documents, making it a powerful tool for working with structured data.

## Key Facts
- XQuery was officially introduced in 2007 by the World Wide Web Consortium (W3C).
- It is based on XPath, a query language for selecting nodes from XML documents.
- XQuery supports dynamic, strong, and static typing disciplines.
- The language is designed to work with XML and, as of version 3.1 (released in 2017), also supports JSON.
- XQuery is classified as a functional programming language and a query language.
- It is a declarative language, meaning it focuses on what to do rather than how to do it.
- XQuery replaces XQL, an earlier XML query language.
- Notable contributors to XQuery include Michael Howard Kay and Mary Fernández.

## FAQs
### Q: What is XQuery used for?
A: XQuery is primarily used for querying and manipulating XML data. It allows users to extract, transform, and manipulate data from XML documents efficiently.

### Q: Who developed XQuery?
A: XQuery was developed by the World Wide Web Consortium (W3C), with contributions from computer scientists like Michael Howard Kay and Mary Fernández.

### Q: What programming paradigms does XQuery support?
A: XQuery supports declarative programming, functional programming, and modular programming paradigms.

### Q: Can XQuery work with JSON?
A: Yes, as of version 3.1 (released in 2017), XQuery supports JSON in addition to XML.

### Q: What is the relationship between XQuery and XPath?
A: XQuery is based on XPath, which is a query language for selecting nodes from XML documents. XQuery extends XPath's capabilities to include more complex queries and transformations.

## Why It Matters
XQuery plays a crucial role in the handling and manipulation of XML data, which is widely used for data storage and exchange on the web. By providing a powerful and flexible way to query and transform XML data, XQuery enables developers to efficiently manage and process structured data. Its support for functional programming principles allows for concise and expressive code, making it easier to write and maintain complex data processing tasks. Additionally, XQuery's ability to work with both XML and JSON (as of version 3.1) makes it a versatile tool for modern data processing needs. Its declarative nature simplifies the process of data extraction and transformation, reducing the need for imperative code and making it accessible to a broader range of users.

## Notable For
- Being a functional programming language specifically designed for querying XML data.
- Supporting multiple typing disciplines, including dynamic, strong, and static typing.
- Extending the capabilities of XPath to include more complex queries and transformations.
- Supporting both XML and JSON data formats, enhancing its versatility.
- Being developed by the World Wide Web Consortium (W3C), ensuring its standardization and widespread adoption.

## Body
### Overview
XQuery is a functional programming and query language designed for querying and manipulating XML data. It was officially introduced in 2007 by the World Wide Web Consortium (W3C) and is based on XPath, a query language for selecting nodes from XML documents.

### Features and Capabilities
- **Functional Programming**: XQuery is a functional programming language, meaning it treats computation as the evaluation of mathematical functions and avoids changing state and mutable data.
- **Declarative Nature**: XQuery is a declarative language, focusing on what to do rather than how to do it. This makes it easier to write and maintain complex data processing tasks.
- **Typing Disciplines**: XQuery supports dynamic, strong, and static typing disciplines, providing flexibility and robustness in data handling.
- **Data Formats**: XQuery is designed to work with XML and, as of version 3.1 (released in 2017), also supports JSON.
- **Programming Paradigms**: XQuery supports declarative programming, functional programming, and modular programming paradigms.

### Development and Contributors
XQuery was developed by the World Wide Web Consortium (W3C). Notable contributors include Michael Howard Kay, a British computer scientist, and Mary Fernández, an American computer scientist and activist.

### Relationship with XPath
XQuery is based on XPath, which is a query language for selecting nodes from XML documents. XQuery extends XPath's capabilities to include more complex queries and transformations, making it a more powerful tool for working with XML data.

### Versions and Updates
- **Version 3.1**: Released in 2017, this version introduced support for JSON, enhancing XQuery's versatility and making it suitable for modern data processing needs.

### Applications
XQuery is widely used for querying and manipulating XML data, making it a valuable tool for data storage and exchange on the web. Its ability to handle both XML and JSON data formats makes it a versatile choice for modern data processing tasks.

## Schema Markup
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  "@type": "Thing",
  "name": "XQuery",
  "description": "A functional programming and query language designed specifically for querying and manipulating XML data.",
  "url": "http://www.w3.org/XML/Query/",
  "sameAs": ["https://www.wikidata.org/wiki/Q185363", "https://en.wikipedia.org/wiki/XQuery"],
  "additionalType": "http://schema.org/SoftwareApplication"
}

## References

1. Freebase Data Dumps. 2013
2. [Source](https://www.w3.org/TR/xquery-3/)
3. [Source](https://pygments.org/docs/lexers/#pygments.lexers.webmisc.XQueryLexer)
4. Quora
5. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)