table does not exist - column does not exist

-- HikaShop version -- : 2.3.5
-- Joomla version -- : 3.4.8
-- PHP version -- : 5.4.45
-- Browser(s) name and version -- : Chrome

Hi.
I have a custom field on product table, called pcscase.
I need to have a mass action that updates the value of the price.
The value of the price should be price_value = (operation) price.price_value * product.pcscase
When i execute this mass action, it says that these tables and columns does not exist,
but when i modify mass action to price_value = (operation) price.price_value * 2 it works
Also when i modify mass action to price_value = (operation) product.pcscase * 2 it works too.
How is it possible that when i multiply this 2 columns, it does not work:
price_value = (operation) price.price_value * product.pcscase