Large XML Document Error

Question

We are using Oracle's XSQL servlet engine 9.0.2.0.0A to query an Oracle Database using xsql:include-owa. This xsql document uses a custom serializer to write the resulting XML to a file on the webserver. We have run into a problem with writing XML documents larger than approximatly 7MB. The file is written but just contains a Malformed XML Document error. We have tried tracking down the problem and it seems to be occuring before the custom serializer is given control of the document. Attached below is the xsql document and the Java source of our serializer if it would be of any help.
-Eric Dalquist
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="simple_transform_xml.xsl" serializer="XMLWriter"?>
<BASE_TAG connection="XXXXXXXX" xmlns:xsql="urn:oracle-xsql">
    <xsql:set-page-param name="save-file" value="XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/applInfo.xml"/>
    <xsql:include-owa >
        STUDEV.STUADMSDSET.P_GET_RECRUIT_INFO('A','C');
    </xsql:include-owa>
</BASE_TAG>-----------------------------------------
* Author:        Eric Dalquist
* E-Mail:        [email protected]
* Date Created:  10-03-2001
* Last Modified: 10-03-2001
* Modified By:   Eric Dalquist
* Description:   This class writes out the contents of the final document produced by the xsql servlet.
package com.mtu.XSQLSerializers;
import java.io.FileOutputStream;
import oracle.xml.xsql.*;
import oracle.xml.parser.v2.XMLDocument;
import org.w3c.dom.Document;
* <P>
*    XMLWriter is an implementation of the abstract XSQLDocumentSerializer class. It is passed a refrence to a DOM Document
*    and the servlet environment. The XMLWriter takes the document and writes it out to the servlet's output stream. There
*    is also the option that the saveFile xsql page parameter can be set to a fully qualified path and file name to write the
*    document to.
* </P>
* <P>
*    Here is an example of setting the saveFile page paramter. This line would be the first tag inside the root xsql servlet tag.
* </P>
* <PRE>
*    &#060;xsql:set-page-param name="save-file" value="/u01/oracle/ias10210/xdk/java/xsql/Repository/Course_List/XMLDocument.xml"/&#062;
* </PRE>
* @author  Eric B. Dalquist
* @version 1.0 10/03/2001
public class XMLWriter implements XSQLDocumentSerializer
    /** the header we send if we are returning XML */
    private static final String MIME_XML = "text/xml";
    /** the name of the page parameter we look for to get the path and name to save the XML document to */
    private static final String ATTR_FILE = "save-file";
     * The serialize is called by the servlet engine and is passed the DOM Docuement result
     * from the XSLT transformation if there was one and a refrence to the XSQL servlet environment
     * @param doc The document representation of the XML output of the xsql servlet.
     * @param env A refrence to the servlet's environment.
     * @throws Throwable Any unhandled error is handled by the servlet by default.
    public void serialize(Document doc, XSQLPageRequest env) throws Throwable
        System.out.print("start ... ");
        FileOutputStream fos = null;
        String reqType = env.getRequestType();
        String saveFile = env.getParameter(ATTR_FILE);
        if (!reqType.equals("Command Line"))
            env.setContentType(MIME_XML);
            ((XMLDocument)doc).print(env.getOutputStream());
            env.getOutputStream().close();
        if (saveFile != null && !saveFile.equals("") && saveFile.indexOf("..") == -1 && saveFile.indexOf("~") == -1)
            fos = new FileOutputStream(saveFile);
            ((XMLDocument)doc).print(fos);
            fos.close();
        System.gc();
        System.out.println("end");
}

Answer 1

Technically DBMS_XMLSAVE and it's alter ego DBMS_XMLQUERY are not considered part of XML DB. DBMS_XMLSAVE and DBMS_XMLQUERY are legacy Java implementations.
In 9.2.x these routines were replaced by DBMS_XMLSTORE and DBMS_XMLGEN which are written in 'C' and should be much faster in most cases and address a number of limitations inherant in the older implementations. DBMS_XMLSTORE and DBMS_XMLGEN are part of XML DB and the minimum supported release for XML DB is 9.2.0.3.0.
DBMS_XMLSAVE issues are addressed in the TECH/XML forum
http://forums.oracle.com/forums/category.jspa?categoryID=51