Errors when using inplace schema evolution

Question

Hi, i have been having some issues when attempting to use inplace schema evolution to add a new element into an existing xsd file currently registered on the database and was looking for some help with this if possible.
Firstly, Oracle details are as follows :
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
"CORE     11.2.0.2.0     Production"
TNS for IBM/AIX RISC System/6000: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - ProductionThe xsd registered on the database is called truncheadtest2.xsd :
<?xml version="1.0" encoding="UTF-8"?>
<!--W3C Schema generated by XMLSpy v2009 sp1 (http://www.altova.com)-->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xdb="http://xmlns.oracle.com/xdb" xdb:storeVarrayAsTable="true">
     <xs:element name="title">
          <xs:simpleType>
               <xs:restriction base="xs:string"/>
          </xs:simpleType>
     </xs:element>
     <xs:element name="clientRiskEventHeader" xdb:defaultTable="EVLN_CLIENTRISKEVENTHEADER">
          <xs:complexType xdb:SQLType="EVLN_CLIENTRISKEVENTHEADER_T">
               <xs:sequence>
                    <xs:element ref="title" xdb:SQLName="TITLE"/>
               </xs:sequence>
          </xs:complexType>
     </xs:element>
</xs:schema>registered via :
BEGIN
  DBMS_XMLSCHEMA.registerSchema(
   SCHEMAURL => 'http://xmlns.kfis.co.uk/testevheader/xsdin/truncheadertest.xsd',
  SCHEMADOC => XDBURIType('/public/web_quotes/header/xsd/test/SchemaTest/truncheadtest2.xsd').getCLOB());
END;i have then created a new xsd, to add the new element to the xsd (using minoccurs to allow backwards compatibility between xml files conforming to the 1st xsd and this new xsd), called truncheadtestfn3.xsd :
<?xml version="1.0" encoding="UTF-8"?>
<!--W3C Schema generated by XMLSpy v2009 sp1 (http://www.altova.com)-->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xdb="http://xmlns.oracle.com/xdb" xdb:storeVarrayAsTable="true">
     <xs:element name="title">
          <xs:simpleType>
               <xs:restriction base="xs:string"/>
          </xs:simpleType>
     </xs:element>
     <xs:element name="forename">
          <xs:simpleType>
               <xs:restriction base="xs:string"/>
          </xs:simpleType>
     </xs:element>
     <xs:element name="clientRiskEventHeader" xdb:defaultTable="EVLN_CLIENTRISKEVENTHEADER">
          <xs:complexType xdb:SQLType="EVLN_CLIENTRISKEVENTHEADER_T">
               <xs:sequence>
                    <xs:element ref="title" xdb:SQLName="TITLE"/>
                    <xs:element ref="forename" minOccurs="0" xdb:SQLName="FORENAME"/>
               </xs:sequence>
          </xs:complexType>
     </xs:element>
</xs:schema>I can run the following code to create the difference doc between the 2 versions of the schema document, without errors:
DECLARE
   schemaDiff XMLType;
   res boolean;
BEGIN
   SELECT xmlDiff
        xdburitype('/public/web_quotes/header/xsd/test/SchemaTest/truncheadtest2.xsd').getXML(),
        xdburitype('/public/web_quotes/header/xsd/test/SchemaTest/truncheadtestfn3.xsd').getXML()
   INTO schemaDiff
   FROM dual;
   IF (dbms_xdb.existsResource('/public/web_quotes/header/xsd/test/SchemaTest/header.xml')) THEN
       dbms_xdb.deleteResource('/public/web_quotes/header/xsd/test/SchemaTest/header.xml');
   END IF;
   res :=
     dbms_xdb.createResource('/public/web_quotes/header/xsd/test/SchemaTest/header.xml',schemaDiff);
     dbms_xmlschema.inPlaceEvolve('http://xmlns.kfis.co.uk/testevheader/xsdin/truncheadertest.xsd',schemaDiff,2);
END;
/ which creates the following xml file:
- <xd:xdiff xsi:schemaLocation="http://xmlns.oracle.com/xdb/xdiff.xsd http://xmlns.oracle.com/xdb/xdiff.xsd" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xdb="http://xmlns.oracle.com/xdb" xmlns:xd="http://xmlns.oracle.com/xdb/xdiff.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <?oracle-xmldiff operations-in-docorder="true" output-model="snapshot" diff-algorithm="global"?>
- <xd:insert-node-before xd:node-type="element" xd:xpath="/xs:schema[1]/xs:element[2]">
- <xd:content>
- <xs:element name="forename">
- <xs:simpleType>
  <xs:restriction base="xs:string" />
  </xs:simpleType>
  </xs:element>
  </xd:content>
  </xd:insert-node-before>
- <xd:append-node xd:node-type="element" xd:parent-xpath="/xs:schema[1]/xs:element[2]/xs:complexType[1]/xs:sequence[1]">
- <xd:content>
  <xs:element ref="forename" minOccurs="0" xdb:SQLName="FORENAME" />
  </xd:content>
  </xd:append-node>
  </xd:xdiff>However, when i then run the inplace schema evolution code for option 1, i get the following error:
Error report:
ORA-22324: altered type has compilation errors
ORA-22328: object "WEB_STAGING"."EVLN_CLIENTRISKEVENTHEADER_T" has errors.
PLS-00215: String length constraints must be in range (1 .. 32767)
ORA-06512: at "XDB.DBMS_XMLSCHEMA_INT", line 173
ORA-06512: at "XDB.DBMS_XMLSCHEMA", line 231
ORA-06512: at line 17
22324. 00000 -  "altered type has compilation errors"
*Cause:    The use of the ALTER TYPE statement caused a compilation error.
*Action:   Correct the error reported and resubmit the statement.I am getting this issue when attempting to add any string value to the existing xsd and i was wondering if you had any idea what the issue was here and how i could resolve this.
Thanks.

Answer 1

Hi,
When you use INPLACE_TRACE flag, it traces the operations that would be performed with option 1.
If you look at the trace file produced in this case, you'll see where the error is coming from :
------------ QMTS Executing SQL ------------
ALTER TYPE "TEST"."EVLN_CLIENTRISKEVENTHEADER_T" ADD ATTRIBUTE "FORENAME" VARCHAR2 CASCADE NOT INCLUDING TABLE DATA
/The mandatory length specification is absent.
I thought adding an explicit xs:maxLength restriction would solve the problem, but it happens the generated DDL still lacks the length specification.
After some tries, I found that the issue seems related to the usage of ref elements in the schema.
On a side note, it's not the first time we see problems associated with ref (Cf. how do i get xml db to work right with imported or included schemas?).
The workaround is to use a named type.
I've also added an xdb:defaultTable annotation to the top-level element ("title") so that the registration process doesn't generate a table for it :
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xdb="http://xmlns.oracle.com/xdb" xdb:storeVarrayAsTable="true">
     <xs:element name="title" xdb:defaultTable="">
          <xs:simpleType>
               <xs:restriction base="xs:string">
                 <xs:maxLength value="200"/>
               </xs:restriction>
          </xs:simpleType>
     </xs:element>
     <xs:simpleType name="forenameType">
          <xs:restriction base="xs:string">
               <xs:maxLength value="30"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:element name="clientRiskEventHeader" xdb:defaultTable="EVLN_CLIENTRISKEVENTHEADER">
          <xs:complexType xdb:SQLType="EVLN_CLIENTRISKEVENTHEADER_T">
               <xs:sequence>
                    <xs:element ref="title" xdb:SQLName="TITLE"/>
                    <xs:element name="forename" type="forenameType" minOccurs="0" xdb:SQLName="FORENAME"/>
               </xs:sequence>
          </xs:complexType>
     </xs:element>
</xs:schema>