Validating XML files against schema in Oracle PL/SQL

Question

I have a requirement to validate an incoming file against an XSD. Both will be on the server file system.

I've looked at dbms_xmlschema, but have had issues getting it to work.

Could it be easier to do it with some Java?
What's the simplest class I could put in the database?

Here's a simple example:

DECLARE
  v_schema_url       VARCHAR2(200) := 'http://www.example.com/schema.xsd';
  v_blob             bLOB;
  v_clob             CLOB;
  v_xml XMLTYPE;
BEGIN
  begin
    dbms_xmlschema.deleteschema(v_schema_url);
  exception
    when others then
     null;
  end;

  dbms_xmlschema.registerSchema(schemaURL => v_schema_url,
                                schemaDoc => '
<xs:schema targetNamespace="http://www.example.com" 
xmlns:ns="http://www.example.com" 
xmlns:xs="http://www.w3.org/2001/XMLSchema" 
elementFormDefault="qualified" attributeFormDefault="unqualified" version="3.0">
<xs:element name="something"  type="xs:string"/>
</xs:schema>',
                                local => TRUE);

  v_xml := XMLTYPE.createxml('<something xmlns="http://www.xx.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xsi:schemaLocation="http://www.example.com/schema.xsd">
data
</something>');

  IF v_xml.isschemavalid(v_schema_url) = 1 THEN
    dbms_output.put_line('valid');
  ELSE
    dbms_output.put_line('not valid');
  END IF;
END;

This generates the following error:

ORA-01031: insufficient privileges
ORA-06512: at "XDB.DBMS_XDBZ0", line 275
ORA-06512: at "XDB.DBMS_XDBZ", line 7
ORA-06512: at line 1
ORA-06512: at "XDB.DBMS_XMLSCHEMA_INT", line 3
ORA-06512: at "XDB.DBMS_XMLSCHEMA", line 14
ORA-06512: at line 12

Critic

Answer 1

Update

XML Schema registration requires following privileges:

grant alter session to <USER>;
grant create type to <USER>; /* required when gentypes => true */
grant create table to <USER>; /* required when gentables => true */

For some reason it's not enough if those privileges are granted indirectly via roles, but the privileges need to be granted directly to schema/user.

Original Answer

I have also noticed that default values of parameters gentables and gentypes raise insufficient privileges exception. Probably I'm just lacking of some privileges to use those features, but at the moment I don't have a good understanding what they do. I'm just happy to disable them and validation seems to work fine.

I'm running on Oracle Database 11g Release 11.2.0.1.0

gentypes => true, gentables => true

dbms_xmlschema.registerschema(schemaurl => name,
                              schemadoc => xmltype(schema),
                              local => true
                              --gentypes => false,
                              --gentables => false
                              );

ORA-01031: insufficient privileges
ORA-06512: at "XDB.DBMS_XMLSCHEMA_INT", line 55
ORA-06512: at "XDB.DBMS_XMLSCHEMA", line 159
ORA-06512: at "JANI.XML_VALIDATOR", line 38
ORA-06512: at line 7

gentypes => false, gentables => true

dbms_xmlschema.registerschema(schemaurl => name,
                              schemadoc => xmltype(schema),
                              local => true,
                              gentypes => false
                              --gentables => false
                              );

ORA-31084: error while creating table "JANI"."example873_TAB" for element "example"
ORA-01031: insufficient privileges
ORA-06512: at "XDB.DBMS_XMLSCHEMA_INT", line 55
ORA-06512: at "XDB.DBMS_XMLSCHEMA", line 159
ORA-06512: at "JANI.XML_VALIDATOR", line 38
ORA-06512: at line 7

gentypes => true, gentables => false

dbms_xmlschema.registerschema(schemaurl => name,
                              schemadoc => xmltype(schema),
                              local => true,
                              --gentypes => false
                              gentables => false
                              );

ORA-01031: insufficient privileges
ORA-06512: at "XDB.DBMS_XMLSCHEMA_INT", line 55
ORA-06512: at "XDB.DBMS_XMLSCHEMA", line 159
ORA-06512: at "JANI.XML_VALIDATOR", line 38
ORA-06512: at line 7

gentypes => false, gentables => false

dbms_xmlschema.registerschema(schemaurl => name,
                              schemadoc => xmltype(schema),
                              local => true,
                              gentypes => false,
                              gentables => false
                              );

PL/SQL procedure successfully completed.

Cartomancy

Answer 2

You must have ALTER SESSION privilege granted in order to register a schema.

Agnesse

Answer 3

here is a piece of code that works for me. user272735's answer is right, I wrote another answer as far as I can't write all the code in a comment (too long).

/* Formatted on 21/08/2012 12:52:47 (QP5 v5.115.810.9015) */
DECLARE
   -- Local variables here
   res          BOOLEAN;
   tempXML      XMLTYPE;
   xmlDoc       XMLTYPE;
   xmlSchema    XMLTYPE;
   schemaURL    VARCHAR2 (256) := 'testcase.xsd';
BEGIN
   dbms_xmlSchema.deleteSchema (schemaURL, 4);
   -- Test statements here
   xmlSchema :=
      xmlType('<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xdb="http://xmlns.oracle.com/xdb"
elementFormDefault="qualified" attributeFormDefault="unqualified">
<xs:element name="root" xdb:defaultTable="ROOT_TABLE">
<xs:complexType>
<xs:sequence>
<xs:element name="child1"/>
<xs:element name="child2"/>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
');
    -- https://mcmap.net/q/1733041/-validating-xml-files-against-schema-in-oracle-pl-sql
    dbms_xmlschema.registerschema(schemaurl => schemaURL,
                                  schemadoc => xmlSchema,
                                  local => true,
                                  gentypes => false,
                                  gentables => false
                                  );
   xmlDoc :=
      xmltype('<root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="'
              || schemaURL
              || '"><child1>foo</child1><child2>bar</child2></root>');
   xmlDoc.schemaValidate ();
   -- if we are here, xml is valid
   DBMS_OUTPUT.put_line ('OK');
exception
    when others then
    DBMS_OUTPUT.put_line (SQLErrm);
END;

Glennieglennis

Answer 4

Once you get past the install issues, there are challenges in some Oracle versions when the schemas get big, particularly when you have schemas that include other schemas. I know we had that issue in 9.2, not sure about 10.2 or 11.

For small schemas like your example, though, it should just work.

Pheasant

Answer 5

Registering the XSD leads to creation of tables, types and triggers. Therefore you need the following grants:

grant create table to <user>;
grant create type to <user>;
grant create trigger to <user>;

Lodgment

Answer 6

If I remember correctly, that error message is given when XDB (Oracle's XML DataBase package) is not properly installed. Have the DBA check this out.

Oba