XML-Type and reference to unavailable DTD causes validation problems

Question

Hi,
I'm fairly new to Oracle's XML features. I've created a view that produces XML from a number of tables. The resulting XML is used to be stored on a web site for download by customers (this is a manual process about once a week via a CMS). It contains a reference to a DTD that is available on the web server, too. This XML must also be stored in the Oracle database. The problem is that the Oracle Server is not allowed to access any web site (Oracle server is in inhouse network with no access allowed to the world outside). So I can't store the XML in an XML-type column, as the Oracle server wants to validate the XML against the referenced DTD. There is an option not to validate the XML. But then I get the error when I try to access the XML afterwards. So up to now I use a CLOB column to store the XML, but then I lose all the benefits of an XML-type column. Is there any workaround?
TIA,
Stefan

Answer 1

In 10.2.0.2.0 The following works
SQL> drop table TEST_XML
  2  /
Table dropped.
SQL> create table TEST_XML (
  2     XML_SEQ number(10) not NULL,
  3     XML_DOC XMLType not NULL
  4  )
  5  /
Table created.
SQL> drop sequence TEST_XML_SEQ
  2  /
Sequence dropped.
SQL> create sequence TEST_XML_SEQ
  2  /
Sequence created.
SQL> create or replace view V_EMP_XML as select
  2         -- Processing Instruction
  3         '<?xml version="1.0" encoding="ISO-8859-1"?>' ||
  4         -- DTD reference
  5         '<!DOCTYPE employees SYSTEM "http://myserver/dtd/employees.dtd">' ||
  6         SYS.XMLTYPE.getClobVal(
  7            XMLElement("employees",
  8               (select XMLAgg(
  9                          XMLElement("emp",
10                             XMLAttributes(
11                                e.EMPNO as "empno",
12                                e.DEPTNO as "deptno"
13                             ),
14                             XMLElement("ename", e.ENAME),
15                             XMLElement("job", e.JOB),
16                             XMLElement("salary", e.SAL),
17                             XMLElement("hiredate", to_char(e.HIREDATE, 'YYYY-MM-DD'))
18                          )
19                       order by e.EMPNO
20                       )
21                from   SCOTT.EMP e
22               )
23            )
24         ) as XML_DOC
25  from   DUAL
26  /
View created.
SQL>
SQL> insert into TEST_XML
  2  (
  3    XML_SEQ,
  4    XML_DOC
  5  )
  6  select TEST_XML_SEQ.NEXTVAL,
  7         XMLType(v.XML_DOC, NULL, 1, 1)
  8  from   V_EMP_XML v
  9  /
1 row created.
SQL> select t.XML_DOC.getClobVal() as RESULT
  2  from   TEST_XML t
  3  where  t.XML_SEQ = 1
  4  /
RESULT
<?xml version="1.0" encoding="ISO-8859-1"?><!DOCTYPE employees SYSTEM "http://my
SQL> select extract(t.XML_DOC, '//emp[@deptno=20]').getClobVal() as RESULT
  2  from   TEST_XML t
  3  where  t.XML_SEQ = 1
  4  /
ERROR:
ORA-31011: XML parsing failed
ORA-19202: Error occurred in XML processing
LPX-00202: could not open "http://myserver/dtd/employees.dtd" (error 101)
Error at line 1
no rows selected
SQL> alter session set events ='31156 trace name context forever, level 2'
  2  /
Session altered.
SQL> select extract(t.XML_DOC, '//emp[@deptno=20]').getClobVal() as RESULT
  2  from   TEST_XML t
  3  where  t.XML_SEQ = 1
  4  /
RESULT
<emp empno="7369" deptno="20"><ename>SMITH</ename><job>CLERK</job><salary>800</s
SQL>