Hey Guys,
I want to set all products "Always Free Shipping" but it seems I need to edit these products one by one.
Is there any way to complete it all?
I've google it, and I followed one of the instruction:

In my zen cart admin go to Tools -> Install SQL Patches

Copy and pate the sql code with my added category ID number into the box and click on the “send” button.

"UPDATE products SET product_is_always_free_shipping = 1 WHERE master_categories_id = xx;"

But it NOT working for me. Anybody has better idea?
Thanks a lot!