title: MySQL: is it possible to group_concat multiple rows?
body: <p>Here's what I want:</p>
  
  <pre><code>attribute_name  attribute_id    attribute_value
  --------------------------------------------------------------------
  Appliances      16, 17, 18, 19  Washer, Dryer, Dishwasher, Microwave
  Consoles        7, 3            PS3, XBox
  </code></pre>
  
  <p>Here's close to what I've got:</p>
  
  <pre><code>attribute_name  attribute_id   attribute_value
  -------------------------------------------------
  Appliances      16             Washer
  Appliances      17             Dryer
  Appliances      18             Dishwasher
  Appliances      19             Microwave
  Consoles        7              PS3
  Consoles        3              XBox
  </code></pre>
  
  <p>...from this query:</p>
  
  <pre><code>  SELECT     a.name AS attribute_name,
  
               av.attribute_value_id, av.value AS attribute_value
  
    FROM       attribute_value av
  
    INNER JOIN attribute a
  
                 ON av.attribute_id = a.attribute_id
  
    WHERE      av.attribute_value_id IN
  
                 (SELECT attribute_value_id
  
                  FROM   property_attribute
  
                  WHERE  property_id = 1)
  
    ORDER BY   a.name;
  </code></pre>
  
  <p>I've had no success with GROUP_CONCAT.  I don't even know what I want is possible.</p>