Input xml to where clause ..

Question

An input XML passed as a parameter to the oracle stored procedure . based on input xml the dynamic predicate( where ) clause need to be build . for example
<map opt="and" >
<map opt="and" >
<condition opt="equal" >
     <key>job_id</key>
     <value>IT_PROG</value>
</condition>
<conditon opt="equal" >
          <key>salary</key>
          <value>9000</value>
</conditon>
</map>
<map opt="or" >
<condition opt="equal" >
          <key>manger_id</key>
          <value>100</value>
</condition>
<conditon opt="like" >
               <key>lastname</key>
               <value>m</value>
</conditon>
</map>
</map>
select * from employees where (job_id='IT_PROG' and salary='9000') or (manager_id = '100' or last_name like '%m%').
please help with pl/sql part of this . i have written a pl/sql which can print the element tag , what changes should i make this code .
The input xml will be dynamic based on the input xml the predicate should be prepared, i want to use oracle dom .
declare
vxml xmltype;
l_xmldoc xmldom.DOMDocument;
l_ndlist xmldom.DOMNodeList;
l_node xmldom.DOMNode;
l_element xmldom.DOMElement;
len number;
BEGIN
vxml:= xmltype('<map opt="and" >
<map opt="and" >
<condition opt="equal" >
     <key>job_id</key>
     <value>IT_PROG</value>
</condition>
<conditon opt="equal" >
          <key>salary</key>
          <value>9000</value>
</conditon>
</map>
<map opt="or" >
<condition opt="equal" >
          <key>manger_id</key>
          <value>100</value>
</condition>
<conditon opt="like" >
               <key>lastname</key>
               <value>m</value>
</conditon>
</map>
</map>
l_xmldoc := xmldom.newDOMDocument(vxml);
l_ndlist := xmldom.getElementsByTagName(l_xmldoc, '*');
len := xmldom.getLength(l_ndlist);
-- loop through elements
for i in 1..len-1 loop
l_node := xmldom.item(l_ndlist, i);
dbms_output.put( xmldom.getNodeName(l_node));
l_node := xmldom.getFirstChild(l_node);
if xmldom.getNodeType(l_node) = xmldom.TEXT_NODE then
dbms_output.put('='|| xmldom.getNodeValue(l_node) || ' ');
end if;
dbms_output.put(' ');
end loop;
dbms_output.put_line('');
END;

Answer 1

>
our application has java front end , the users have option to select multiple filter values . the frond end developers will send an xml construct as the one i have showed . based on the input xml i have to apply those filters on a table . so i thought using xml dom and parse the xml and make a dynamic sql from that .
>
why java app needs to send XML? Let it create SQL and execute it.
Of course you can do it in PL/SQL but it less convenient comparing to Java.
If you can extract values from XML, then just create SQL for them, assign bind vars and execute it dynamically.
Yes, you will have to implement lots of IF logic.
Advise: Use bind variables as placeholders for values to avoid injection attacks. Do not concatenate values into your dynamic SQL.