How to change the color of an attribute (size) that is not available?

Question

WordPress

Hi everyone, please tell me how to make woo so that the sizes of goods that are out of stock have a different color.
So that without clicking on them, it was clear whether they are available or not

Answer 1

What is the amount of data?
It can be divided into 2 tables, in the first one to store the id, the owner of the comment, the date, and other "light" data. In the second table, assign the corresponding comment id its tags, text, etc.
Be sure to set indexes in the first table and in the second by id.
I misunderstood the question, sorry. To filter BEFORE record in a DB - it is natural.

Answer 2

If the comment is filtered anyway, then why store it in the database? Plus it is more opportunities to inject the code to you.