title: HSQLDB ROWNUM compatibility with Oracle
body: <p>THe <a href="http://hsqldb.org/doc/2.0/changelist_2_0.txt">HSQLDB changelog</a> states that <code>ROWNUM()</code> was added in <code>v2.2.0</code> which I am using without any problems when running integration tests against the in-memory HSQLDB.</p>
  
  <p>However I want to run the same tests against a real Oracle 10g database, but the query fails because the pseudo-column is called <code>ROWNUM</code>. Is there an easy way write a single query string that works in both environments?</p>