Error in product class updateCharacteristics

-- HikaShop version -- : 2.3.4
-- Joomla version -- : 3.3
-- PHP version -- : 5
-- Error-message(debug-mod must be tuned on) -- : #1054 Unknown column 'b.characteristic_id' in 'field list' SQL=SELECT b.characteristic_id FROM j3_hikashop_variant AS v LEFT JOIN j3_hikashop_characteristic AS c ON v.variant_characteristic_id = c.characteristic_id WHERE v.variant_product_id = 298 AND c.characteristic_parent_id = 0

Hi,

I'm making a module for Joomla that adds products and variants to HikaShop and I get the SQL error. It's coming from the file administrator/components/com_hikashop/classes/product.php in the function updateCharacteristics line 646. As you can see it's trying to get 'b.characteristic_id' but both included tables are 'c' and 'v'.

I've fixed it locally and it seems fine.