Convert Product Code To Product Id

Some addon's I have base on Product ID, however my CSV file has only Product Code. Is it any function which will be "translated" Product Code to ID?

Eventually is there any way to add new fields to product? Then I can import products and export with updated ID and field which I need for other import?

In the phpmyadmin run

UPDATE cscart_products SET product_code = product_id;

What if product code is numbers and letters?

In CSV I have only product Code, I can't use ID instead.

In CSV I have only product Code, I can't use ID instead.

Right, product code is used as main key. Try to leave product id column and make all values in the product code column empty. Not tested, make backup