Joomla custom xml options

[Jonny]

Im playing with the joomla com_menus/models/forms/item.xml File.I would like to use the feature of a SQL form field type as stated in joomla docs here.http://docs.joomla.org/SQL_form_field_typeBut i just cant seem to figure out how to get more than just one value.My code is this:\[code\]<field name="link" type="sql" default="" class="articleselectbox" label="Select an article" query=" SELECT #__content.id, #__content.alias, #__content.title, #__content.catid, #__categories.id, #__categories.alias FROM #__content LEFT JOIN #__categories ON #__content.catid=#__categories.id ORDER BY #__content.title" key_field="alias" value_field="catid" /> \[/code\]What i need is this as a final value:\[code\]#__categories.alias / #__content.id - #__content.alias . html\[/code\]So the oputput would be:\[code\]poultry/12-organic-chicken-farming.html\[/code\]I can get one value but the documentation dosent describe how to retrieve any more than that. Anyone have any ideas on how this could be achieved please?Cheers.Jonny