import from excel or similar

Hi,

It's not yet possible. We are currently looking into adding that to HikaShop.

You won't be able to add categories via phpmyadmin as you would have to calculate the category_left and category_right values following a tree structure. It's kind of complicated to do by hand but it has the advantage of speeding up things for processing.

You could add products via phpmyadmin, but you have to understand the structure of the database. In order to handle several files, images, files, categories, related products for a product (basically everything on the right column with you edit a product via HikaShop's interface), the data is in different tables:
hikashop_product for the product main information
hikashop_price for the prices of products
hikashop_product_category for links between products and categories
hikashop_file for files and images

So it's not that easy to do but it's possible.