just read your coffee induce thought just before i posted..

the x and y are related to the product.. and the price is related to
the x and y or a selected product

hence the thought of

productgridid,productid,productx,producty

this would have to have the product reference and the productx and
producty entered manually.. didnt think for the 20 enteries the (x *
y) worth splitting again in to productgridxid,productid,productx and
productgridyid,productid,producty
then as u said dont join them select them out of each table then get
the corrosponding prices from a third table, and then populate an
array i presume for manipulation

pricegridid,productid,productidxid,productyid,pric e

so combining the productgird and the x and y and the pricegrid price
for each of the x and y then list them

i am glad its making you scratch your head

generally rule is ... that once a product is set up, that the sizes
wont change only the prices for all x and y's and since the price and
constant increment it becomes a bum ache...

looking forward to your idea etc