Need to update the xml clob-pls pls help!

Question

my xml is stored as blob, i can view,do string manipulation and churn out data etc...but now i have a request where i need to find some particualr node and modify its value.
here is what i m doing now which works.
select compressor2.blob_decompress2(xml_data) into l_blob
from tablename where id=2008890;
clob_data := utl2.blob2clob(l_blob);
parser := xmlparser.newParser;
xmlparser.parseClob(parser, clob_data);
doc := xmlparser.getDocument(parser);
nl := xmldom.getElementsByTagName(doc, '*');
len := xmldom.getLength(nl);
dbms_output.put_line('Length : ' || len);
tag_name := 'Node Verson : ' || xmldom.getVersion(doc)|| '<br>';
for counter in 0..len-1
loop
tag_name := '';
node := xmldom.item(nl, counter);
parent_node := xmldom.getParentNode(node);
child_node := xmldom.getfirstchild(node);
tag_name := 'Parent Name : ' || xmldom.getNodeName(parent_node) || '<br>';
tag_name := tag_name || 'Node Name : ' || xmldom.getNodeName(node) || '<br>';
IF xmldom.getNodeType(child_node) = xmldom.TEXT_NODE THEN
tag_name := tag_name || 'Node Value : ' || xmldom.getNodeValue(child_node)|| '<br>';
ELSE
tag_name := tag_name || 'Node Value : Node has child.No Node value.' || '<br>';
END IF;
tag_name := tag_name || 'Node Type : '||xmldom.getNodeType(child_node) || '<br>';
ele_name := xmldom.getDocumentElement(doc);
child_nl := xmldom.getElementsByTagName(ele_name,'*');
IF xmldom.isNull(doc) THEN
htp.p('Document is null');
ELSE
htp.p(tag_name);
END IF;
end loop;
b_blob := utl.clob2blob(tag_name);
select compressor2.blob_compress2(b_blob) into b_blob2 from dual;
insert into xupdate values (2008890,b_blob2);
i still need to know how to update the xml clob... i want to know how to find the particular node and then modify the clob with the new value. rest i can update the table.
pls pls help..on this.

Answer 1

my oracle version.
10.2.0.1.0
i want to update here..
<?xml version="1.0" encoding="utf-8"?>
<TestData xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
     <Status>CompletedNormally</TestCompletionStatus>
     <ComputerName>DUILT10</ComputerName>
     <StartTime>2008-03-19T15:12:23</StartTime>
---Some more noded----
<Parameters>
          <RangeMeasured>
               <Name>PDissBol-5[C]</Name>
               <Min>1.22</Min>
               <Max>1.36</Max>
               <Units>W</Units>
          </RangeMeasured>
          <TextMeasured>
               <Name>ComputerName</Name>
               <Value>DUILT10</Value>
          </TextMeasured>
          <RangeMeasured>
               <Name>TrackError25[C]To-5[C]</Name>
               <Min>0.031</Min>
               <Max>0.041</Max>
               <Units>dB</Units>
          </RangeMeasured>
          <RangeMeasured>
               <Name>Power-5[C]</Name>
               <Min>1.988</Min>
               <Max>1.061</Max>
               <Units>dBm</Units>
          </RangeMeasured>
---some more noded---
</Parameters>
</TestData>
the file is huge.
what i need to chang==>
I 1st need to find this PDissBol-5[C] within the <Parameters> Node and then change its <Min> and <Max>
and then update the table.
pls pls suggest.