title: How to escape wildcard characters in "like" clause?
body: <p>How can I escape the wildcard characters in a like clause?</p>
  
  <p>E.g.:</p>
  
  <pre>
  select foo from Foo as foo where foo.bar like '%' || :filter ||'%'
  </pre>
  
  <pre>
  query.setParameter("filter", "%");
  query.list(); 
  // I'd expect to get the foo's containing the '%' in bar, not all of them!
  </pre>
  
  <p>Any ideas?</p>