SQL extension instructions
To use the SQL extension in a stylesheet, you need to define a namespace prefix (for
         example sql) in the extension-element-prefixes attribute of the
            xsl:stylesheet element, and
         to map this prefix to a namespace URI, conventionally http://saxon.sf.net/sql.
         This namespace must be bound in the Configuration to the implementation class
            net.sf.saxon.option.sql.SQLElementFactory. This binding can be done either
         by calling ProfessionalConfiguration.setExtensionElementNamespace(), or by means of an entry
         in the configuration
         file.
This changed in Saxon 9.2. In Saxon 9.1 and earlier releases it was necessary to use a namespace ending in "/net.sf.saxon.sql.SQLElementFactory". It is still possible to use the same namespace, but it must now be bound explicitly.
This extension defines eight new stylesheet instructions described in the following sections:
See the Example for an example of the use of these SQL extension elements.