The Item Id is unique, each item has an item id, unique, a class id, a color id and a size id, this last three not being unique. I'll put the class, color and size names for clarity, only the numeric ID is saved in the items table.

ItemID ClassID   Class Name   ColorID Color SizeID Size  Stock
1      1         SHIRT        1       BLUE  1      S     50
2      1         SHIRT        1       BLUE  2      M     25
3      1         SHIRT        2       RED   1      S     30
4      2         PANTS        5       DENIM 10     32X32 10
5      2         PANTS        5       DENIM 11     32X34 5   

So I keep stock for every distinct Item. Of course it's flexible enough to ignore such differentiation, since you can have an OSFA (One Size Fits All) size, and an ASSORTED size for the same purpose

>Hi,
>Feel glad to recieve your msg.
>Does your program keep the stock qty of same item id, but diff colour, diff size and diff style? Or, you keep it as one item? e.g.