Re: group functions

Q1 - D, final answer.

• If your where clause only returns rows that have null commisions, then null + anything should give you null, and sum(null) is also null.
  -> select sum(null) + sum(1), sum(null) from dual;
  

Q2 - B+C, you probably missed Filler/Miller, since it is less obvious. Your where clause assumes time 0, but your data doesn't show the time, and based on the information you gave, implies a value > 0

hth Received on Sat Dec 02 2006 - 08:23:33 CST