XML/XSD question (using ODI)

Question

Hi all.
I have posted this in the ODI forum as well, but this may be a more proper place to ask for help.
I'm working on a new dwh solution where the main source of data will come from XML-files. The problem is that we are having difficulties with the use of abstract types in the xsd-file. We currently use ODI to read the XML-files and to store the data in our database, but all fields from the XML-files are not visible in the target tables.
The problem can be simplified like this example:
We have a main element, testElement, which can contain one or more publications.
Publication is of type PublicationType, and PublicationType is an abstract that contains title, author and date.
We have four other types which extends PublicationType; BookType, MagazineType, NewspaperType and AdsType. They all contain additional fields.
XSD-file
<?xml version="1.0" encoding="UTF-8"?>
<schema xmlns="http://www.w3.org/2001/XMLSchema"
targetNamespace="urn:testing:kontroll:example:oppgave:v1"
xmlns:tns="urn:testing:kontroll:example:oppgave:v1"
xmlns:xdb="http://xmlns.oracle.com/xdb"
elementFormDefault="qualified">
<element name="testElement" type="tns:TestElementType" xdb:defaultTable="TEST_TAB" />
<complexType name="TestElementType">
<sequence>
<element name="publication" type="tns:PublicationType" minOccurs="1"
maxOccurs="unbounded" />
</sequence>
</complexType>
<complexType name="PublicationType" abstract="true">
<sequence>
<element name="title" type="string"/>
<element name="author" type="string" minOccurs="0"
maxOccurs="unbounded" />
<element name="date" type="string"/>
</sequence>
</complexType>
<complexType name="BookType">
<complexContent>
<extension base="tns:PublicationType">
<sequence>
<element name="ISBN" type="string"/>
<element name="publisher" type="string"/>
</sequence>
</extension>
</complexContent>
</complexType>
<complexType name="MagazineType">
<complexContent>
<extension base="tns:PublicationType">
<sequence>
<element name="editor" type="string"/>
<element name="period" type="string" minOccurs="0"
maxOccurs="1"/>
</sequence>
</extension>
</complexContent>
</complexType>
<complexType name="NewspaperType">
<complexContent>
<extension base="tns:PublicationType">
<sequence>
<element name="daily" type="boolean"/>
<element name="owner" type="string" minOccurs="0"
maxOccurs="1"/>
</sequence>
</extension>
</complexContent>
</complexType>
<complexType name="AdsType">
<complexContent>
<extension base="tns:PublicationType">
<sequence>
<element name="company" type="string"/>
<element name="article" type="string" />
</sequence>
</extension>
</complexContent>
</complexType>
</schema>
XML-file
<?xml version="1.0" encoding="UTF-8"?>
<tns:testElement xmlns:tns="urn:testing:kontroll:example:oppgave:v1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:testing:kontroll:example:oppgave:v1 ExampleXMLSchema.xsd ">
<tns:publication xsi:type="tns:BookType">
<tns:title>Boken</tns:title>
<tns:author>Arne Svendsen</tns:author>
<tns:date>2001</tns:date>
<tns:ISBN>78979797</tns:ISBN>
<tns:publisher>The Company Ltd</tns:publisher>
</tns:publication>
<tns:publication xsi:type="tns:MagazineType">
<tns:title>Fancy Magazine</tns:title>
<tns:author>Mads Madsen</tns:author>
<tns:date>2011</tns:date>
<tns:editor>Svante Svantesen</tns:editor>
<tns:period>weekly</tns:period>
</tns:publication>
</tns:testElement>
When tables are generated in the database through ODI I'm not getting all the attributes present in the xml-file.
Can anybody tell me if this should work (and, if yes, why it doesn`t)? Or if the XSD/XML looks wrong in some way?
Is this a known limitation in Oracle or ODI etc.?
Any pointers to documentation describing similar problems would also be helpful.
Thanks,
Bjørn

Answer 1

Hi, Bjørn,
When tables are generated in the database through ODI I'm not getting all the attributes present in the xml-file.I don't know ODI, so I'm just curious here : what tables are generated? Is there one table per extented type (+ child tables for repeating elements), or just one Publication table with missing columns?
I've looked at the other thread you mentioned on the ODI forum, and saw that you'd also want to store XML files in an XMLType table.
I tested the schema registration in the database to see how Oracle reacts to the structure, and it looks OK, type extensions are supported.
SQL> begin
  2   dbms_xmlschema.registerSchema(
  3     schemaURL => 'ExampleXMLSchema.xsd'
  4   , schemaDoc => bfilename('TEST_DIR', 'ExampleXMLSchema.xsd')
  5   , local => true
  6   , genTypes => true
  7   , genTables => true
  8   , enableHierarchy => dbms_xmlschema.ENABLE_HIERARCHY_NONE
  9   );
10  end;
11  /
PL/SQL procedure successfully completed
SQL> insert into test_tab
  2  values (xmltype('<?xml version="1.0" encoding="UTF-8"?>
  3  <tns:testElement xmlns:tns="urn:testing:kontroll:example:oppgave:v1"
  4                   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  5                   xsi:schemaLocation="urn:testing:kontroll:example:oppgave:v1 ExampleXMLSchema.xsd ">
  6    <tns:publication xsi:type="tns:BookType">
  7      <tns:title>Boken</tns:title>
  8      <tns:author>Arne Svendsen</tns:author>
  9      <tns:date>2001</tns:date>
10      <tns:ISBN>78979797</tns:ISBN>
11      <tns:publisher>The Company Ltd</tns:publisher>
12    </tns:publication>
13    <tns:publication xsi:type="tns:MagazineType">
14      <tns:title>Fancy Magazine</tns:title>
15      <tns:author>Mads Madsen</tns:author>
16      <tns:author>Arne Svendsen</tns:author>
17      <tns:date>2011</tns:date>
18      <tns:editor>Svante Svantesen</tns:editor>
19      <tns:period>weekly</tns:period>
20    </tns:publication>
21  </tns:testElement>'))
22  ;
1 row inserted
Querying as relational data :
SQL> select x.*
  2  from test_tab t
  3     , xmltable(xmlnamespaces(default 'urn:testing:kontroll:example:oppgave:v1'),
  4       'for $i in /testElement/publication
  5        return element r {
  6          $i/child::*
  7        , element pubtype {
  8            typeswitch($i)
  9              case element(publication, BookType)      return "Book"
10              case element(publication, MagazineType)  return "Magazine"
11              case element(publication, AdsType)       return "Ads"
12              case element(publication, NewspaperType) return "Newspaper"
13              default return "Publication"
14          }
15        }'
16       passing t.object_value
17       columns title   varchar2(500) path 'title'
18             , authors varchar2(500) path 'string-join(author,",")'
19             , pubdate number(4)     path 'date'
20             , isbn    number(13)    path 'ISBN'
21             , editor  varchar2(500) path 'editor'
22             , period  varchar2(500) path 'period'
23             , pubtype varchar2(30)  path 'pubtype'
24       ) x
25  ;
TITLE                 AUTHORS                        PUBDATE           ISBN EDITOR                PERIOD      PUBTYPE
Boken                 Arne Svendsen                     2001       78979797                                   Book
Fancy Magazine        Mads Madsen,Arne Svendsen         2011                Svante Svantesen      weekly      Magazine