Error when inserting xml with xsi:noNamespaceSchemaLocation

Question

Hello,
Hopefully this isn't a stupid question....
I am currently using Oracle 9.2.0.6.0 to try out XML.
I haven't been able to get our DBAs to set up XML DB in its entirety so I just have the basics, i.e. I have access to the xmltype object but none of the packages like DBMS_SCHEMA and DBMS_XDB. Therefore, I haven't been able to register any schemas in the database.
So what I'd like to know is why do I get an ORA-21700 error when I try to load an xml document which has the 'xsi:noNamespaceSchemaLocation' attribute'. If I take this out of the XML document, it loads.
From my initial reading, I got the impression that registering a schema in order to validate documents was an optional, although probably an ideal, step to take.
So another way of phrasing this subject might be: can one insert xml documents without the use of a schema?
The example code is shown below.
dbase> INSERT INTO MY_TABLE( id , message_type , status , rcvd_time, filename , xmlcol)
2 VALUES ( 1, 0 , 'RECEIVED', sysdate , 'tempfilename' ,
3 xmltype('<ExampleXML xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
4 xsi:noNamespaceSchemaLocation = "ExampleXML.xsd">
5 <tag1>
6 <tag2 attr1="something">Some data
7 </tag2>
8 </tag1>
9 </ExampleXML>')
10 );
xmltype('<ExampleXML xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
ERROR at line 3:
ORA-21700: object does not exist or is marked for delete
ORA-06512: at "SYS.XMLTYPE", line 0
ORA-06512: at line 1
dbase> ed
Wrote file afiedt.buf
1 INSERT INTO MY_TABLE ( id , message_type , status , rcvd_time, filename , xmlcol)
2 VALUES ( 1, 0 , 'RECEIVED', sysdate , 'tempfilename' ,
3 xmltype('<ExampleXML xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
4 >
5 <tag1>
6 <tag2 attr1="something">Some data
7 </tag2>
8 </tag1>
9 </ExampleXML>')
10* )
dbase> /
1 row created.
The xmlcol column was created simply as an xmltype column.

Answer 1

Basically using XMLType without XML DB is almost impossible in 9.2.x. Please have the DBA's install XML DB by running the script $ORACLE_HOME/rdbms/admin/catqm.sql. They can follow the installing XDB instuctions in the XML DB Developer's guide.
What is actually happening here is that the PARSER is hard wired to always check is a document that contains an noNamespaceSchemaLocation or schemaLocation tag is associated with an XML Schema that has been registered with Oracle XML DB. If is is, special action is takem, if it isn't then no special action is taken. Unfortunately for various arcane technical reasons if the the XDB repository is not present the check fails totally. Even if we fixed this bug, which has been marked not feasible to fix in the past, there are many other issues with the inbuilt XML technology having dependancies on the presence of the XML DB repository and XDB database user.
So the net/net is don't use XMLType or any XML related features in 9.2.x or later unless XML DB is installed. It is extremenly likely at this point in time that XML DB will become a mandatory component of the next release of the database. At that point you will no longer have an option. It will be automatically installed when a database is created or updated and there will be no way of un-installing it.