title: ALTER COLUMN token TYPE varchar('800');
body: <p>How to convert that '800'(String) to 800(Integer)</p>
  <p>I had use</p>
  <pre><code>ALTER COLUMN token TYPE varchar('800'::integer)
  </code></pre>
  <p>or</p>
  <pre><code>ALTER COLUMN token TYPE varchar(CAST('800' as integer))
  </code></pre>
  <p>but still not working</p>
  <p>Please help, thanks</p>