XQuery can be used for a wide variety of XML processing needs. As such, different XQuery implementations provide customized functions and settings for specific use cases. This chapter looks at some of the implementation-specific aspects of XQuery.
The XQuery specification consists of a core set of features that all implementations are required to support. Supporting these features is known as minimal conformance. In addition, there are a handful of optional features that are clearly defined and scoped. These optional features are listed in Table 25-1.
|Module||Support for library modules and module imports||“Assembling Queries from Multiple Modules”|
|Schema Aware||Support for schema imports in the prolog and ||Chapter 14|
|Typed Data||Support for typed element and attribute nodes||Chapter 14|
|Static Typing||Detection of all static type errors in the analysis phase||Chapter 15|
|Higher-Order Function||Support for function items, inline function expressions, and dynamic function calls||Chapter 23|
|Serialization||Ability to serialize query results||“Serializing Output”|
In addition to these seven features, some aspects of the core language are either implementation-dependent or implementation-defined. Implementation-defined features are those where the implementer is required to document the choices she has made. For example, the list of supported collations or additional built-in ...