SQL Question - two queries

Question

One works, One does not.....Why?
SQL> select m.sales_rep,
2 sum(decode(to_char(m.enddate,'YYYY'),'2006',sum(d.qty*d.billrate),0)) as sales_2006,
3 sum(decode(to_char(m.enddate,'YYYY'),'2005',sum(d.qty*d.billrate),0)) as sales_2005
4 from tempnet.sysuser s, tempnet.invmast m, tempnet.invdetail d
5 where trunc(s.shortid) = trunc(m.sales_rep)
6 and m.invoice = d.invoice
7 and m.enddate >= '01-jan-2006'
8 and m.enddate <= '01-jan-2007'
9 and m.posted = 'Y'
10 and s.status = 'A'
11 and s.title = '1000232'
12 /*and m.sales_rep is not null*/
13 group by m.sales_rep;
select m.sales_rep,
ERROR at line 1:
ORA-00937: not a single-group group function
SQL>
ORA-00937 not a single-group group function
Cause: A SELECT list cannot include both a group function, such as AVG, COUNT, MAX, MIN, SUM, STDDEV, or VARIANCE, and an individual column expression, unless the individual column expression is included in a GROUP BY clause.
Action: Drop either the group function or the individual column expression from the SELECT list or add a GROUP BY clause that includes all individual column expressions listed.
SQL> select c.firstname||' '||c.lastname as name,
2 sum(decode(to_char(a.enddate,'YYYY'),'2006',(b.qty*b.billrate),0)) as inv_sales_2006,
3 sum(decode(to_char(a.enddate,'YYYY'),'2005',(b.qty*b.billrate),0)) as inv_sales_2005
4 from tempnet.invmast a, tempnet.invdetail b, tempnet.sysuser@devuser_tn8 c
5 where a.invoice = b.invoice
6 and (b.line_type in ('RH','OH','PH','DH')
7 or (b.line_type = 'CH'
8 and b.description = 'Buyout'))
9 and trunc(a.enddate) >= to_date('01-jan-2005')
10 and trunc(a.enddate) <=to_date('01-jan-2007')
11 and a.posted = 'Y'
12 and c.shortid = a.sales_rep
13 and c.title = '1000232'
14 and c.status = 'A'
15 group by c.firstname||' '||c.lastname
16 /
NAME INV_SALES_2006 INV_SALES_2005
Alex Boufidis 5059635.99 5181504.95
Anthony Tillman 1510936.49 186792.043
Bob Golder 857637.413 0
Brian Joyce 1285177.53 25005.9
Chris Batten 526838.688 0
Clark McHenry 159057.095 0
Craig Ward 2108217.81 736089.318
Daniel Fried 372353.863 0

Answer 1

One works, One does not.....Why?You've SUM function twice in the first query, but not in the second one..
sum(decode(to_char(m.enddate,'YYYY'),'2006',sum(d.qty*d.billrate),0))