title: Select all rows where there is not a specific value in a different table
body: <p>This is a wordpress installation, but I think the question is more of a general sql question.  First off, my sql skills are not great (I don't even know if I'm following the correct format for illustrating the db).</p>
  
  <p>I've got two tables:</p>
  
  <pre><code>wp_posts :
  
      ID (pk)  |   post_name  |  ...
  ----------------------------
      45       |    "Hello"
      91       |    "Funny"
      16       |    "Wheat"
  
  wp_postmeta :
  
      post_id (fk)  |    meta_key      |   meta_value  | ...
  ------------------------------------------------
      45            |    "_edit_lock"  |   5789789834
      45            |    "fizzbizz"    |   "foobar"
      91            |    "_something"  |   "teve"
  </code></pre>
  
  <p>I would like to select all rows in wp_posts where there is NO corresponding row in wp_postmeta where meta_key = "fizzbizz"</p>
  
  <p>I originally had this query, but someone pointed out that it would not retrieve ID = '16' in the above case. How would I correctly write the query?</p>
  
  <pre><code>$pageposts = $wpdb-&gt;get_results("
      SELECT * FROM wp_posts p 
      JOIN wp_postmeta m 
      ON p.ID = m.post_id 
      WHERE m.meta_key &lt;&gt; 'fizzbizz' 
      ORDER BY p.post_date DESC;
  ");
  </code></pre>