Variant table constraint

Hi I'm trying to build a Variant table to be able to move some of the complexity from constraint net to a table.

But I am running into a problem, take for example below:

Objects:
X is_a (300)Thing.

Condition:
table Thing
   (
      WIDTH_PROD = X.WIDTH_PROD,
      HEIGHT_PROD = X.SPC_HEIGHT_PROD
   ).

Restrictions:
false.

This works, but I need to check in intervals so i made some characteristics and put them im table:

WIDTH_PROD_FROM

WIDTH_PROD_TO

HEIGHT_PROD_FROM

HEIGHT_PROD_TO

Here comes my problem when i want to compare:

WIDTH_PROD_FROM > X.WIDTH_PROD,

WIDTH_PROD_TO < X.WIDTH_PROD_TO,

HEIGHT_PROD_FROM > X.SPC_HEIGHT_PROD,

HEIGHT_PROD_TO < X.SPC_HEIGHT_PROD,

How would I go about this problem of having a product specification saying 10-7500 mm width and height 800-9000 ,product X with H 500 and W 900 is then ok. The above does not make scense to have in table i know but i have a lot of other combinations as well :-)

Thanks in advance.