title: SQL 'AND' or 'OR' comes first?
body: <p>I have the following query:</p>
  
  <pre><code>SELECT * FROM MUFFIN_TYPES MT
    WHERE MT.flavor IS NULL 
      OR MT.flavor IS NOT NULL 
      AND MT.additionDate IS NOT NULL
  </code></pre>
  
  <p>Without clarifying parenthesis this is confusing. Would <code>MT.flavor IS NULL OR MT.flavor IS NOT NULL</code> always evaluate to true? Or would it evaluate as <code>MT.flavor IS NULL (OR MT.flavor IS NOT NULL AND MT.additionDate IS NOT NULL)</code>?</p>
  
  <p>I couldn't find any documentation on the matter. I the latter of the two options, but I'm not sure.</p>
  
  <p>Note: I'm using Oracle Pl/SQL.</p>