D(node-metadata-equality-string,name:http://www.sleepycat.com/2002/dbxml,=,'sgml.xml',V(edge-attribute-equality-string,xref.@xrefid,=,'top4')) V(edge-attribute-equality-string,xref.@xrefid,=,'top4') D(node-metadata-equality-string,name:http://www.sleepycat.com/2002/dbxml,=,'sgml.xml',U)