title: IsDate Function in SQL evaluates invalid dates as valid
body: <p>I am running a SQL Statement against imported data from Excel Files.
  In this SQL I am checking if the users have entered dates properly by using IsDate function. Since this is a raw data that hasn't been converted yet, all dates are stored in a varchar data type field.</p>
  
  <p>In some circumstances IsDate returns 1 (valid date) when there is clearly an incorrect date format entered by the user.</p>
  
  <p>For Example:</p>
  
  <pre><code>07/001/2012
  
  2012-07-002
  
  007/002/2012
  </code></pre>
  
  <p>Any Suggestions on how to handle this problem?</p>
  
  <pre><code>SELECT *
    FROM tblImport
   WHERE (ISDATE(dt) = 0 
          AND (dt is not null AND dt &lt;&gt; ''))
  </code></pre>
  
  <p>Thanks!</p>
  
  <p>p.s. Smacking users' did not help.</p>