I am trying the following query. Could you please give me some direction or answer?
I have 2 tables. The first one is CLIENTS with with client_number as the key and city or location. The second one is BILLING with biil_number as the key, Client_number, date_of_bill and billing_amount.
How can I get the following report with a single SQL (if possible)
Client-number Location Sum(Amount)
Of course each client can have many bills in a pre_determined period of time.
If there is no billing records for a client ZERO shoud be displayed.