Remove text attributes from products

i need remove certain TEXT attribute from all products of one category,
from admin options names manager and options values manager, i find many ways to add or remove other type attributes, but i don't find a way to remove text attributes
is it possible to do this?

Use the Attributes Controller.

by using the Attributes Controller, i can delete the text attributes one by one, but i have too many products in one category and too many attributes
i want to delete text attributes (option id 3 and 9 and 17) of all products from one category (category id 6)
it seems i couldn't do this by attrributes controller?

i want to run this in phpmyadmin, but i only want to delete them from category id 6
DELETE from zen_products_attributes WHERE options_id= 3

what do i add the category id?

for the dropdown attributes, i can do this by attributes controller, thats very easy, but i wonder why i coudn't do this to text attributes?

by using attributes controller, for the DROP DOWN attributes,
i can delete all option values to one category of products for one option name, i can also delete matching attribute from all products for one option
but i don't find a way to do this to TEXT attributes
any ideas?