Sorry, I've made a mistake.
I registered that M55slik_v0.2.
Just when writing to you I've copied first line and forgot to change CommonTypesSti_v0.2.xsd to M55slik_v0.2.

I've never did XSD validation before. So here is great possibility that I'm doing something wrong.

Someone told me that I need first to create schema based XML before checking if it is valid. Something like this:

l_Xml := l_Xml.createSchemaBasedXML('M55slik_v0.2.xsd');
l_Xml.schemavalidate();

In this case I got error ORA-31000: Resource 'M55slik_v0.2.xsd' is not an XDB schema document

But what is strange that this error is raised not by createSchemaBasedXML('M55slik_v0.2.xsd');
But by schemavalidate();

If I change some letter in name M55slik_v0.2.xsd lets say to M55slik_v0.3.xsd then I get the same ORA-31000 but on l_Xml.createSchemaBasedXML('M55slik_v0.3.xsd');

So it seems that it should be registered("createSchemaBasedXML" did not throw an exception). But "schemavalidate" thinks otherwise and throws ORA-31000. Why?

What it is more strange that if I intentionally made xml not valid then Oracle throws exception about that. So validation is happening. But why I get ORA-31000 when xml seems to be valid?

In one example I found that dbms_xdb.createResource is called.
And after that

Dbms_XmlSchema.RegisterSchema('CommonTypesSti_v0.2.xsd', xdbURIType('/public/M55slik_v0.2.xsd').getClob());

Is this is different from just registering schema directly without dbms_xdb.createResource first?

Can you please tell all necessary steps that should be done to correctly validate xml. I've searched a lot on internet but still can't get it working right.

Thank you

I've tried your eaxpamle on https://asktom.oracle.com/pls/apex/f?p=100:11:0::::P11_QUESTION_ID:9529444000346870090

And it works fine.

So it seems that only registerSchema and isSchemaValid is enough.
But cant get it working with my XSD and XML :(

In my first review I posted link to all XSD and XML example. One XSD file is quite big to paste it here.

There is the link https://www.vmi.lt/cms/documents/10162/6703244/SPECIFIKACIJA_MAI_55.zip/c86d3e1d-b081-47d6-a9a1-b021f6dcc85c

This is a zip file. In folder MAI_55_LT_XSD-v0.2 there are XSD files.
I need to test only M55Slik_v0.2.xsd
But it uses CommonTypesSti_v0.2.xsd, IsoTypesSti_v0.2.xsd, M55TypesSti_v0.2.xsd. In these files there are only types. Element is in M55Slik_v0.2.xsd


And my code is as simple as DBMS_XMLSCHEMA.registerSchema for all these four XSD and then isSchemaValid('M55slik_v0.2').

XML file to be tested is in folder "XML pavyzdžiai" named MAI55_SLIK_XML_v0.1.xml.

One note! In xml file there is M55TypesSti_v0.1.xsd, but I assume it should be M55TypesSti_v0.2.xsd.

Oracle says is not valid.
If I try

y := x.createSchemaBasedXML('M55slik_v0.2.xsd');
y.schemavalidate();

Then I get ORA-31000

BEGIN
  Dbms_XmlSchema.RegisterSchema('M55slik_v0.2.xsd', '<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="a" type="xs:string"/>
</xs:schema>');
END;
/
DECLARE
  l_Xml XMLTYPE := XMLTYPE('<a></a>'); 
BEGIN
  Dbms_Output.Put_Line(l_Xml.isSchemaValid('M55slik_v0.2')); 
  Dbms_Output.Put_Line(l_Xml.isSchemaValid('M55slik_v0.2.xsd')); 
END;
/

0
1

The order of xsd files to register is as follows:
CommonTypesSti_v0.2.xsd
IsoTypesSti_v0.2.xsd
M55TypesSti_v0.2.xsd
M55Slik_v0.2.xsd

is there is any tool or API available in oracle to get XSD from XML?

the below demo was from Oracle 21c EE (21.3) - Here is my XML

<?xml version="1.0"?>
<ROWSET>
  <DEPT>
    <DEPTNO>10</DEPTNO>
    <DNAME>ACCOUNTING</DNAME>
    <LOC>NEW YORK</LOC>
    <EMP_LIST>
      <EMP_ROW>
        <EMPNO>7782</EMPNO>
        <ENAME>CLARK</ENAME>
        <JOB>MANAGER</JOB>
        <MGR>7839</MGR>
        <HIREDATE>09-JUN-1981 00:00:00</HIREDATE>
        <SAL>2450</SAL>
      </EMP_ROW>
      <EMP_ROW>
        <EMPNO>7839</EMPNO>
        <ENAME>KING</ENAME>
        <JOB>PRESIDENT</JOB>
        <HIREDATE>17-NOV-1981 00:00:00</HIREDATE>
        <SAL>5000</SAL>
      </EMP_ROW>
      <EMP_ROW>
        <EMPNO>7934</EMPNO>
        <ENAME>MILLER</ENAME>
        <JOB>CLERK</JOB>
        <MGR>7782</MGR>
        <HIREDATE>23-JAN-1982 00:00:00</HIREDATE>
        <SAL>1300</SAL>
      </EMP_ROW>
    </EMP_LIST>
  </DEPT>
</ROWSET>

got XSD generated for it using https://www.liquid-technologies.com/online-xml-to-xsd-converter
then registered it to database like this

demo@PDB1> declare
  2     l_clob clob;
  3  begin
  4     l_clob := q'# <?xml version="1.0" encoding="utf-8"?>
  5  <!-- Created with Liquid Technologies Online Tools 1.0 (https://www.liquid-technologies.com) -->
  6  <xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  7    <xs:element name="ROWSET">
  8      <xs:complexType>
  9        <xs:sequence>
 10          <xs:element name="DEPT">
 11            <xs:complexType>
 12              <xs:sequence>
 13                <xs:element name="DEPTNO" type="xs:unsignedByte" />
 14                <xs:element name="DNAME" type="xs:string" />
 15                <xs:element name="LOC" type="xs:string" />
 16                <xs:element name="EMP_LIST">
 17                  <xs:complexType>
 18                    <xs:sequence>
 19                      <xs:element maxOccurs="unbounded" name="EMP_ROW">
 20                        <xs:complexType>
 21                          <xs:sequence>
 22                            <xs:element name="EMPNO" type="xs:unsignedShort" />
 23                            <xs:element name="ENAME" type="xs:string" />
 24                            <xs:element name="JOB" type="xs:string" />
 25                            <xs:element minOccurs="0" name="MGR" type="xs:unsignedShort" />
 26                            <xs:element name="HIREDATE" type="xs:string" />
 27                            <xs:element name="SAL" type="xs:unsignedShort" />
 28                          </xs:sequence>
 29                        </xs:complexType>
 30                      </xs:element>
 31                    </xs:sequence>
 32                  </xs:complexType>
 33                </xs:element>
 34              </xs:sequence>
 35            </xs:complexType>
 36          </xs:element>
 37        </xs:sequence>
 38      </xs:complexType>
 39    </xs:element>
 40  </xs:schema> #';
 41
 42     dbms_xmlschema.registerSchema('http://www.oracle.com/mydemo.xsd' ,
 43                     schemaDoc => l_clob );
 44  end;
 45  /

PL/SQL procedure successfully completed.

demo@PDB1> select table_name,xmlschema,storage_type
  2  from user_xml_tables ;

TABLE_NAME           XMLSCHEMA                                STORAGE_TYPE
-------------------- ---------------------------------------- --------------------
ROWSET2806_TAB       http://www.oracle.com/mydemo.xsd         OBJECT-RELATIONAL

then tried to insert the above xml to the object relational table using dbms_xmlstore, but ended error like this

demo@PDB1> declare
  2     ctx DBMS_XMLSTORE.ctxType;
  3     l_xmltype xmltype;
  4     l_clob clob;
  5     n number;
  6  begin
  7     l_clob := '<?xml version="1.0"?>
  8  <ROWSET>
  9    <DEPT>
 10      <DEPTNO>10</DEPTNO>
 11      <DNAME>ACCOUNTING</DNAME>
 12      <LOC>NEW YORK</LOC>
 13      <EMP_LIST>
 14        <EMP_ROW>
 15          <EMPNO>7782</EMPNO>
 16          <ENAME>CLARK</ENAME>
 17          <JOB>MANAGER</JOB>
 18          <MGR>7839</MGR>
 19          <HIREDATE>09-JUN-1981 00:00:00</HIREDATE>
 20          <SAL>2450</SAL>
 21        </EMP_ROW>
 22        <EMP_ROW>
 23          <EMPNO>7839</EMPNO>
 24          <ENAME>KING</ENAME>
 25          <JOB>PRESIDENT</JOB>
 26          <HIREDATE>17-NOV-1981 00:00:00</HIREDATE>
 27          <SAL>5000</SAL>
 28        </EMP_ROW>
 29        <EMP_ROW>
 30          <EMPNO>7934</EMPNO>
 31          <ENAME>MILLER</ENAME>
 32          <JOB>CLERK</JOB>
 33          <MGR>7782</MGR>
 34          <HIREDATE>23-JAN-1982 00:00:00</HIREDATE>
 35          <SAL>1300</SAL>
 36        </EMP_ROW>
 37      </EMP_LIST>
 38    </DEPT>
 39  </ROWSET>' ;
 40     l_xmltype := xmltype( l_clob, schema=> 'http://www.oracle.com/mydemo.xsd');
 41      l_xmltype.schemavalidate;
 42
 43     ctx := DBMS_XMLSTORE.newContext('ROWSET2806_TAB'); -- Get saved context
 44      n := DBMS_XMLSTORE.insertXML(ctx, l_xmltype);
 45     dbms_output.put_line( ' n ==> '|| n );
 46      commit;
 47
 48  end;
 49  /
        declare
*
ERROR at line 1:
ORA-31011: XML parsing failed
ORA-19202: Error occurred in XML processing
LPX-00222: error received from SAX callback function
ORA-06512: at "SYS.DBMS_XMLSTORE", line 78
ORA-06512: at "SYS.DBMS_XMLSTORE", line 88
ORA-06512: at line 44

so is it not possible to persist the xml to object relational table using dbms_xmlstore API ? any workaround possible to this?