Id's Restfull Web Service

I need to retrieve the data from one table with two primary keys. Can you please let me know how I need to pass the id in the following URL?

http://localhost:8080/project/webresources/org.thirdg.rest.application.config.competition/

Following XML:

<?xml version="1.0" encoding="UTF-8"?> 
   <competitions> 
       <competition> 
           <centralPositionlat>41.699295000000000</centralPositionlat> 
           <centralPositionlong>-8.752064000000000</centralPositionlong> 
           <competitionPK> 
               <competitionName>Super competition</competitionName> 
               <edition>First Edition 2015</edition> 
           </competitionPK> 
           <description>Test Competition</description> 
       </competition>