Hi, John.

>It is a routine to generate necesary records for example, once user try to create a matrix item (fashion products) with selected size/colour gorup, system should auto-generate all necessary records (n number of colour X n number of size) to stock_status table in order to store qty of each particular item with different colour and size.

Hmmm... This is something akin to the data structure itself in my opinion. Given a specified new matrix, the involved records should be in place. In this case, I think a trigger should be the best approach. It doesn't seem something related with a business rule. It's just a mathematical formula.

However, you can create a store procedure instead of an automatic trigger, and call this SP from you business object, to be able to apply any special logic in the future, like color/size combinations for which certain pairs don't apply or such.

Anyway, I'm not sure if the records for any size/color combination should exist until some stock quantity have being produced... But this is something functional and it doesn't relates with your original question. 8-)

Hope this helps,