title: MYSQL Updating multiple fields from fields of another table
body: <p>Scenario:</p>
  
  <p>I have an application that has a config table which stores the config data for each website thats uses the application. I have added a couple of extra columns to the config table and rolled this out to all applications. I have since updated these new columns with data that needs to be the same on all the config tables.</p>
  
  <p>How would I go about doing this?</p>
  
  <p>My first thought would be to duplicate the table and do the following:</p>
  
  <pre>UPDATE `config` SET `config`.`new1` = `tmp_config`.`new1`, `config`.`new2` = `tmp_config`.`new2` LEFT JOIN `tmp_config` ON (`tmp_config`.`tmp_id` = `config`.`id`)</pre>
  
  <p>Would this have the desired affect.</p>