Learn XQUERY with Real Code Examples
Updated Nov 20, 2025
Explain
XQuery is optimized for querying and transforming XML documents.
It uses XPath expressions as its foundation for navigating XML structures.
Commonly used in enterprise systems, content repositories, and applications requiring structured document processing.
Core Features
FLWOR (For-Let-Where-Order-Return) expressions
XPath path navigation
Strong support for hierarchical data
Typed variables and sequences
Document construction and transformation
Basic Concepts Overview
XPath expressions
Sequences and nodes
FLWOR expressions
Types and variables
XML document construction
Project Structure
src/ - XQuery modules
xml/ - XML documents
lib/ - reusable functions
tests/ - query tests
docs/ - documentation and schemas
Building Workflow
Write XQuery modules (.xq)
Load XML data into processor/database
Run FLWOR queries for extraction
Transform documents with constructors
Output XML/JSON/text results
Difficulty Use Cases
Beginner: basic XPath queries
Intermediate: FLWOR loops and transformations
Advanced: modular XQuery systems
Expert: XML database optimization
Enterprise: metadata-driven workflows and pipelines
Comparisons
More powerful than XPath for querying
More readable than raw DOM manipulation
More specialized than SQL for hierarchical data
Less general-purpose than Python or Java
Often paired with XML databases for best performance
Versioning Timeline
2002 – Initial W3C drafts
2007 – XQuery 1.0 release
2010s – Adoption in XML databases
2014 – XQuery 3.0
2020s – Continued use in enterprise XML systems
Glossary
Node: basic XML data unit
Sequence: ordered list of items
FLWOR: main query expression structure
XPath: XML navigation language
Element Constructor: builds new XML nodes