title: Checking if a value exists in drupal database
body: <p>I'm making a form in drupal and want to check if an email already exists in my database. </p>
  
  <pre><code>  db_insert('CASL_SUBBED')
      -&gt;fields(array(
  
  
        'email' =&gt; $form_state['values']['email'],//email
        'ip' =&gt; $ip55,//ip
        'substatus' =&gt; $subbed,
        'datetime' =&gt; $sDate,//date and time
  </code></pre>
  
  <p>That's my code for inserting into the database, but I want to see if the email already exists before I insert this into it. Is there anyway to do this? Thanks.</p>