title: Mysql delete all posts that have a given meta_key
body: <p>I have a wordpress site that has some meta_key's asigned to my posts. I want to delete all posts in mysql that has the <code>meta_key</code> value <code>acest_meta</code>. With this SQL command : </p>
  
  <pre><code>SELECT `post_id`
  FROM `wp_postmeta`
  WHERE `meta_key` 
  LIKE 'acest_meta' 
  ORDER BY `wp_postmeta`.`post_id` ASC
  </code></pre>
  
  <p>i can see all the id's that contain that given meta_key but i don't have a delete check box neer. I see a message on top that say "Current selection does not contain a unique column. Grid edit, checkbox, Edit, Copy and Delete features are not available." How can i delete all those posts ?</p>