title: Get second occurrence with regexp_substr
body: <p>I can't achieve to make sqlfiddle work so here is my simple code : </p>
  
  <pre><code>select REGEXP_SUBSTR(' EG SUZ SG SIN blabla ', '^(\s?[A-Z]{2} [A-Z]{3}\s?){2}') from dual;
  </code></pre>
  
  <p>I want to get <code>SG SIN</code>. I know <code>REGEXP_SUBSTR</code> got a parameter used to get the nth occurrence but when I write </p>
  
  <pre><code>select REGEXP_SUBSTR(' EG SUZ SG SIN blabla ', '^(\s?[A-Z]{2} [A-Z]{3}\s?){2}'),1,2) from dual;
  </code></pre>
  
  <p>it returns nothing and <code>1,1</code> returns <code>EG SUZ SG SIN</code> so my guess is that the occurrence is not rightly splitted,but I don't know why, can you explain me?</p>