Escaped ampersand still causes LPX-00242 in xmltype.transform

Question

Running Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - 64bit Production
Collecting input from web form, and fetching via SQLX functions to then transform into html and plain text documents. If the "&" is inputted... the SQLX functions does escape it to "&"... but the LPX-00242 error is still raised when sending to xmltype.transform.
A simple test case:
set define off;
declare
l_xsl xmltype;
l_xml xmltype;
begin
l_xsl := xmltype('<?xml version="1.0"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text"/>
<xsl:template match="/">
Hello <xsl:value-of select="//name"/>
</xsl:template>
</xsl:stylesheet>');
l_xml := xmltype('<test><name>Jane&amp;John Doe</name></test>');
dbms_output.put_line(l_xml.transform
                                    (l_xsl
                                    ).getclobval ());
end;the above code raises this exception:
ORA-31011: XML parsing failed
ORA-19202: Error occurred in XML processing
LPX-00241: entity reference is not well formed
Error at line 3
ORA-06512: at "SYS.XMLTYPE", line 138
ORA-06512: at line 20If I rerun the above block... but change the xml string to <test><name>Jane &amp;amp; John Doe</name></test>
I now get the following exception:
Error at line 2
ORA-31011: XML parsing failed
ORA-19202: Error occurred in XML processing
LPX-00242: invalid use of ampersand ('&') character (use &amp;)
Error at line 3
ORA-06512: at "SYS.XMLTYPE", line 138
ORA-06512: at line 20If I change the xml string to <test><name>Jane &amp;amp;amp; John Doe</name></test>.. no exceptions and displays the following:
Hello Jane &amp;amp; John Doe
any reason why the SQLX function escaping is not sufficient and I need to double-escape it? The working version is not ideal, since I now have to decode the entity reference back to it's character, otherwise the entity reference code is displayed in the content.
Edited by: pl_sequel on Sep 7, 2011 2:12 PM

Answer 1

Hi tsuji,
Interesting discussion, really, but I fail to see how the way we're generating the XMLType instance in the first place is important for any subsequent transformation.
You said :
That part is well noticed. And that precisely poses problem.and,
[6.2] But the working (at least for this sample) of the latter but not the former using xmltype() precisely pose the problem of either xmltype().transform() implementation contains bug [...]Could you explain again what you think works and what doesn't?
I may be missing something but all these appear to work correctly :
SQL> var xsldoc varchar2(4000)
SQL> begin
  2   :xsldoc := '<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  3  <xsl:output method="text"/>
  4  <xsl:template match="/">Hello <xsl:value-of select="//name"/>
  5  </xsl:template>
  6  </xsl:stylesheet>';
  7  end;
  8  /
PL/SQL procedure successfully completed
SQL> set define off
SQL> select xmltransform(
  2           xmlelement("test", xmlelement("name", 'Jane&John Doe'))
  3         , :xsldoc
  4         ).getclobval() as result
  5  from dual
  6  ;
RESULT
Hello Jane&John Doe
SQL> select xmltransform(
  2           xmltype('<test><name>Jane&amp;John Doe</name></test>')
  3         , :xsldoc
  4         ).getclobval() as result
  5  from dual
  6  ;
RESULT
Hello Jane&John Doe
SQL> select xmltype(
  2           '<test><name>Jane&amp;John Doe</name></test>'
  3         ).transform(xmltype(:xsldoc)).getclobval() as result
  4  from dual
  5  ;
RESULT
Hello Jane&John Doe
SQL> select xmlelement("test",
  2           xmlelement("name", 'Jane&John Doe')
  3         ).transform(xmltype(:xsldoc)).getclobval() as result
  4  from dual
  5  ;
RESULT
Hello Jane&John Doe
In any case, you know well there is a something fishy going on, one way of looking at it or another.Yes, I agree. For sure, Oracle XSLT processors are not bug-free.
For the case we're looking at now, the essence of the XMLType datatype is probably more to blame than the XSLT processor though.
A little off-topic addendum about the method="html" output :
SQL> select xmltransform(xmlelement("test",
  2           xmlelement("name", 'Jane&John Doe')
  3         ),'<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  4  <xsl:output method="html" encoding="iso-8859-15" indent="yes"/>
  5  <xsl:template match="/"><html><head/><body><p><xsl:value-of select="//name"/></p></body></html>
  6  </xsl:template>
  7  </xsl:stylesheet>').getclobval()
  8  as result
  9  from dual;
RESULT
<html>
<head>
  <meta http-equiv="Content-Type" content="text/html" charset="iso-8859-15">
  </meta>
</head>
<body>
  <p>Jane&#38;John Doe</p>
</body>
</html>
Not perfect but the method seems supported too.
Edited by: odie_63 on 11 sept. 2011 20:43