title: Incorrect integer value when importing csv into a table via mysql workbench
body: <p>ERROR 1366: 1366: Incorrect integer value: '' for column 'subcategory_id' at row 1
  SQL Statement:</p>
  
  <pre><code>INSERT INTO `db`.`shelf` (`shelf_id`, `model_code_name`, `customer_friendly_name`, `sku_code`, `description`, `unitmeasure_id`, `category_id`, `subcategory_id`, `colour`, `size`, `vendor_id`) 
  VALUES ('919025', '', 'MS919025', 'NULL', '1', '3', '31', '', 'W1800*D900*H724MM', '10', '')
  </code></pre>