title: combining mysql AND OR queries in Codeigniter
body: <p>I want to combine AND OR mysql queries in CI. I have already seen this thread: <a href="http://codeigniter.com/forums/viewthread/92818/" rel="noreferrer">http://codeigniter.com/forums/viewthread/92818/</a>.
  But they don't provide the exact solution there.</p>
  
  <p><strong>How do I create the following query using strictly the CI framework?</strong> (I can create the query easily without the brackets but then it is not the same query.)</p>
  
  <pre><code>SELECT * FROM `Persons` WHERE
  LastName='Svendson' AND Age="12" AND
  (FirstName='Tove' OR FirstName='Ola' OR Gender="M" OR Country="India") 
  </code></pre>
  
  <p>P.S.: This is just a sample query even if it makes no sense &amp; Do not suggest writing the entire OR part of the query inside a single <code>where()</code>.</p>
  
  <p><strong>EDIT:</strong> Basically I want the implementation of the following simple query:</p>
  
  <pre><code>SELECT * FROM `table` WHERE field1='value1' AND (field2='value2' OR field3='value3') 
  </code></pre>