In my table, I have records that contain Customer, Invoice, Total ... Initially, the records will be something like this:

Customer Invoice Total

Customer A Invoice 1 10
Customer A Invoice 1 20
Customer A Invoice 1 30 = 60

Customer B Invocie 2 15
Customer B Invocie 2 25
Customer B Invocie 2 30 = 70

Customer A Invoice 3 20
Customer A Invoice 3 20
Customer A Invoice 3 20 = 60

Customer B Invoice 4 10
Customer B Invoice 4 10 = 20

What i want for my query is to display these

Customer Sub Total
Customer A 120
Customer B 90

Sub Total, is the one that i do not know abt.. totalling up all the totals, based on diff customer.. any idea?

thanks..