1、XMLType
drop table xmlExample;

create table xmlExample
(
  ID varchar2(32),name varchar2(200),data XMLType
);

insert into XMLExample values(sys_guid(),\'Exec\',\'<students><student><number>000001</number><name>黎明</name></student><student><number>000002</number><name>赵怡春</name></student></students>\');

insert into XMLExample values(sys_guid(),\'Exec\',xmlType.createXML(\'<students><student id="1"><number>000001</number><name>黎明</name></student><student id="2"><number>000002</number><name>赵怡春</name></student></students>\'));

select * from xmlExample;

2、关系和XML转换
从XML中查询得到关系结果（如果节点不存在，则检索出NULL，不会报错）
查询（别名不可少）
select i.data.extract(\'//student/name\').getStringVal() as stuname, id from xmlExample i

select i.data.extract(\'//student/name/text()\').getStringVal() as stuname, id from xmlExample i

select i.data.extract(\'//student[@id>1]/name\').getStringVal() as stuname, id from xmlExample i

select extractvalue(data,\'/students/student[@id=1]/name\') as name from xmlExample
（只能返回一个记录）

select extractValue(value(i),\'/name\') xx from xmlexample x, table(XMLSequence(extract(x.data,\'/students/student/name\'))) i;

从关系表得到XML
select xmlforest(name,height) from student