I'm trying this code:
Select C.CustomerNum
, C.Coupon
, C.name
, C.Surname
, Sum(P.Points)
From customers C
Join Points P
On P.CustomerNum = C.CustomerNum
Where C.Coupon = 'xxx-xxx-xxx-x';
I'm getting error:
Msg 8118, Level 16, State 1, Line 1 Column 'C.CustomerNum' is invalid in the select list because it is not contained in an aggregate function and there is no GROUP BY clause.