title: Get age between the current year and birthdate, gives **"Conversion failed when converting date and/or time from character string."**
body: <p>I need to get names who are <code>age &gt;=70</code> from a table PERSON and Column BIRTHDATE(varchar(8)). </p>
  
  <p>Just trying this query before i start doing to display age >=70.</p>
  
  <pre><code>select DATEDIFF (year , person.BirthDate, GETDATE()) as Age, * from person
  </code></pre>
  
  <p>This query gives </p>
  
  <blockquote>
    <p>"Conversion failed when converting date and/or time from character string."</p>
  </blockquote>
  
  <p>How should i do this? I really cant think off. Thanks</p>