Re-uploading data advanced import

Hi, I have already uploaded around 200 products via Advanced importer.

If I re-upload that same list of products but with the categories different will it overwrite my previous products with the new category or will it just create new products?

e.g. first upload product has 3 categories.
I want to modify ALL products I have just uploaded so they now have 1 cat
Do I delete all and re-upload or just re-upload and let it overwrite?

Thanks

Answered my own question, I'm going to assume it looks for the product_sku in the database and if exists then UPDATE if not then CREATE.

Made updating my list a breeze, thanks for the import plugin I'd have been here for days without it

That's fine Karl!

Have a nice weekend!

Sincerely, Giang