Working Draft

Date: Jun. 7, 2001
Link: http://www.w3.org/TR/xquery/
Source Author or Organization: W3C

This specification defines XML Query Language (XQuery), a query language that uses XML structure to express intelligent queries across all structured and semistructured XML data sources. XQuery is originally derived from the XML query language Quilt, and builds on useful features incorporated from several other languages.

In XQuery, a query is represented as an expression. Several types of expression, with varying structure and appearance, are supported. This document describes the main expression forms: path expressions (which are based upon XPath syntax), element constructors, For Let When Return (or FLWR, pronounced "flower") expressions, expressions involving functions and arithmetic operators, quantified expressions, conditional expressions, and expressions used for modifying or testing datatypes.

The capabilities of XQuery are designed to become increasingly useful as more data resides in XML format, and as distinctions between different data sources (such as documents and databases) blur.