Designers of XQuery may have considered nested sequences unnecessary for the manipulation of document contents.

XQuery contains a superset of XPath expression syntax to address specific parts of an XML document.

Where the element and attribute names are known in advance, an XML-like syntax can be used; in other cases, expressions referred to as dynamic node constructors are available.

Features for updating XML documents or databases, and full text search capability, are not part of the core language, but are defined in add-on extension standards: XQuery Update Facility 1.0 supports update feature and XQuery and XPath Full Text 1.0 supports full text search in XML documents.

As such, its capabilities overlap with XSLT, which was designed expressly to allow input XML documents to be transformed into HTML or other formats.

They share the same data model (XDM), type system, and function library, and both include XPath 2.0 as a sublanguage.

Both languages have similar expressive power, though XSLT 2.0 has many features that are missing from XQuery 1.0, such as grouping, number and date formatting, and greater control over XML namespaces.

Usability studies have shown that XQuery is easier to learn than XSLT, especially for users with previous experience of database languages such as SQL.

XSLT is currently stronger than XQuery for applications that involve making small changes to a document (for example, deleting all the NOTE elements).

XQuery has no equivalent to this coding pattern, though in future versions it will be possible to tackle such problems using the update facilities in the language that are under development.

[citation needed] XSLT offers two complementary mechanisms in this area: the dynamic matching of template rules, and the ability to override rules using xsl:import, that make it possible to write applications with multiple customization layers.

However, many large applications take advantage of this capability by using XSLT to read, write, or modify stylesheets dynamically as part of a processing pipeline.

The XQueryX representation of XQuery code is rather verbose and not convenient for humans, but can easily be processed with XML tools, for example transformed with XSLT stylesheets.

[20][21] The EXPath Community Group[22] develops extensions to XQuery and other related standards (XPath, XSLT, XProc, and XForms).

XQuery 3.1 de facto deprecates JSONiq as it has added full support for JSON.