title: Incorrect integer value: '' for column
body: <p>What wrong in the following query?
  I want to copy some fields from one table to another.</p>
  
  <pre><code>INSERT INTO `dle_post_plus` 
  (
     `news_id`, `news_read`, `allow_rate`, `rating`, 
     `vote_num`, `votes`, `view_edit`, `access`, 
     `editdate`, `editor`, `reason`, `user_id`
  ) 
  SELECT `id`, `news_read`, `allow_rate`, `rating`, 
     `vote_num`, `votes`, `view_edit`, `access`, 
     `editdate`, `editor`, `reason`, `user_id` 
  FROM `dle_post` 
  LEFT JOIN dle_users 
    ON (dle_post.autor=dle_users.name)
  </code></pre>
  
  <p>erro:</p>
  
  <pre><code>#1366 - Incorrect integer value: '' for column 'editdate' at row 1
  </code></pre>