Product codes

-- HikaShop version -- : 2.6.1

After exploring several e-commerce solutions, I'm looking around for another more suitable solution and I'm playing around with Hikashop (because I need a customer input field for 'color', I'll switch to a paid version after finishing the look-around). What I really don't understand is the idea behind product-codes.

My customer has around 200 products with all 3-6 variants. I like the way to manage the variants (and the easy CSV management ! ). However (example) variant-1 has internal product code 123, variant-2 has 456 and variant -3 has 789. Everybody in the office is familiar with these internal codes and the back office administration is organized in this way.

I'm probably wrong but as far as I understood the Hikashop philosophy is that (following my example), the product code should be 123 and the variants should be called 123_X, 123_Y and 123_Z. If I'm right this means I've to create a cross-reference list between Hika product codes and the codes in use in the organization (btw the real codes are internal product codes linked to EAN). I cannot expect my customer to change his complete back office and logistic procedures because of a webshop product coding system.

Am I right, or do I miss something?

Thanks for your reply. It really helps!

Just to be certain:
Suppose I've a category 'coffee cups'
Product X is 'espresso cup' and this cup is available in 'black' and 'white' (besides the color and price, the specs for both products are equal).

I created a product 'espresso cups' (in category 'coffee cups') and left the product code blank.(called 'main' in the CSV)
After creating 'characteristics', I made two product variants:
1x for 'black' with my own product code 123
1x for 'white' with another product code 456 (both are called 'variant' in the CSV)

It looks to me that relations between 'main' and 'variants' are based on the product_name_alias (and not on the product code).
So a product code for the so called 'main' product description is not necessary at all.

Am I right or is my approach wrong?