The strange behavior of ISSCHEMAVALID member function of XMLTYPE

 s

I ran this code

DECLARE

   XMLDOC       XMLTYPE;

   XMLSCHEMA    XMLTYPE;

   SCHEMAURL    VARCHAR2 (256) := 'testcase.xsd';

BEGIN

   BEGIN

      DBMS_XMLSCHEMA.DELETESCHEMA (SCHEMAURL, 4);

   EXCEPTION

      WHEN OTHERS

      THEN

         NULL;

   END;

   -- 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>

');

--   DBMS_XMLSCHEMA.REGISTERSCHEMA (SCHEMAURL   => SCHEMAURL,

--                                  SCHEMADOC   => XMLSCHEMA,

--                                  LOCAL       => TRUE,

--                                  GENTYPES    => FALSE,