[PS 1.7.4.0] Products order attributes sorting

[gianlucarinaldi3]

Hello everyone.
I'm facing a problem with attribute's sorting.
The shop has different sizes attributes: numeric (from 1 to 45, but also decimal such as 4,5 - 6,5 etc) and alphabetical (S M L XL etc).
There are 75 of these, and I can't manually edit them on via BO: I try to sort them but then when refreshing the page they come back to the initial order.

So I tried to do that via code, editing the file classes/Product.php

I kinda made it editing the code like so:
ORDER BY ag.`position` ASC, al.`name` DESC, agl.`name` ASC, ag.`id_attribute_group` ASC';
So numeric integers and alphabetics works just fine.

BUT

if I have a product which has either numeric values and decimal, the sorting doesn't work.
To have an idea: https://shop.maisonoperative.com/it/Sneakers/721-2771-New-Balance-2900000126374.html#/437-taglia-10/679-colore-yellow

What am I doing wrong?
Thanks to everyone, and stay safe.

Edited April 7, 2020 by gianlucarinaldi3
wrong grammar (see edit history)