---特殊字符转换
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function process_xml(old_xml in varchar2) return varchar2 as
new_xml varchar2(1000);
begin
select replace(old_xml, '<', '<') into new_xml from dual;
select replace(new_xml, '>', '>') into new_xml from dual;
select replace(new_xml, '&', '&') into new_xml from dual;
select replace(new_xml, '''', ''') into new_xml from dual;
select replace(new_xml, '"', '"') into new_xml from dual;
SELECT regexp_replace(new_xml, '^(\W)*|(\W)*$', '')
INTO new_xml
FROM dual;
return new_xml;
exception
when others then
return 'ERROR!';
end process_xml;