title: Updating MySQL table rows based on data in another column
body: <p>I have a Magento table that looks like this:</p>
  
  <pre><code>value_id  entity_type_id  attribute_id   entity_id   value
  189       2               19               20        MR 
  190       2               20               20        Bob
  191       2               21               20         
  192       2               22               20        Steel 
  193       2               23               20         
  194       2               24               20         
  195       2               26               20        London
  196       2               27               20         
  197       2               28               20         
  198       2               30               20        E84 6DD 
  199       2               31               20         
  200       2               32               20        01600786546
  201       2               36               20         
  202       2               19               21         
  203       2               20               21        Alice 
  204       2               21               21         
  205       2               22               21        Smith
  206       2               23               21         
  207       2               24               21         
  208       2               26               21        Manchester
  209       2               27               21         
  210       2               28               21         
  211       2               30               21        M4 56T 
  212       2               31               21         
  213       2               32               21        01278 865214 
  </code></pre>
  
  <p>What I need to do is move the phone number up one row - so where the attribute_id is equal to 32, I need to move the value field of that row into the value field where the attribute_id is equal to 31. </p>
  
  <p>I imagine I'll need to set some variables, but I have no idea where to begin. Any guidance would be much appreciated!</p>