From my table model , how to know Rate field why not link to my YearMonth ?

[paulyeo11]

Hi All

Below is my table model , look like the YearMonth is suppose to link with my Rate field. 

But from the below Table , it show that the Rate Field is not not link with YearMonth field.

Hope some one can advise me where go wrong ?

Paul

[Arthur_Fong]

You have a sample app?