title: MYSQL: diff between tables
body: <p>I have two tables:</p>
  
  <ul>
  <li><p>products</p></li>
  <li><p>products_tmp</p></li>
  </ul>
  
  <p>The <code>products_tmp</code> table has less fields. But all the fields that are in <code>products_tmp</code> are in products.</p>
  
  <p>On import of data I populate the <code>products_tmp</code> table and after that I need to do 3 things:</p>
  
  <ol>
  <li><p>check the new products in <code>products_tmp</code> that are not in products (get ids) (DONE)</p></li>
  <li><p>check the old products in products that are not in <code>products_tmp</code> (get ids for later deletion) (DONE)</p></li>
  <li><p>check for differences on the rest. Both tables have a product-hash unique identifier.</p></li>
  </ol>
  
  <p>And I need to check differences in fields <code>title</code>, <code>text</code>, <code>price</code>, <code>photos</code> and <code>category_id</code>. And getting the tmp ids, so I can then update the products table with new values.</p>
  
  <p>Is it possible to do the diff only in mysql?</p>