The main motivation for using XQuery is for querying XML databases. Most commercial relational database
systems now offer a way to keep and select information in XML but some XML native databases have been developed.
eXist-db
[65] is an open source database management system that
stores XML data according to the XML data model and features efficient index-based XQuery processing.
XQuery can be called from the command line with the Saxon jar library [83]. For example, calling the query Example 6.1 and giving
white
as value of the $color
parameter can be done as follows:
java -cp /path/to/the/SAXON.jar net.sf.saxon.Query -s WineCatalog.xml \ -q WineCatalog.xq color=white > whites.html