title: Operator precedence in regular expressions
body: <p>What is the default operator precedence in Oracle's regular expressions when they don't contain parentheses?</p>
  
  <p>For example, given</p>
  
  <pre><code> H|ha+
  </code></pre>
  
  <p>would it be evaluated as <code>H|h</code> and then concatenated to <code>a</code> as in <code>((H|h)a)</code>, or would the <code>H</code> be alternated with <code>ha</code> as in <code>(H|(ha))</code>?</p>
  
  <p>Also, when does the <code>+</code> kick in, etc.?</p>