Formatting output like matrix

Question

Suppose i have following table
sales_data
Salesman varchar2(20)
Product varchar2(15)
quantity number
The table contains sales figure of various salesmen for different products.Suppose there are products like
Butter,cream,powder,chocolate etc.
A particular saleman may not be dealing in a particular product say "salesman 'john' does not have any sales figure for product 'butter' , but he has sales for another product say 'cream' ,
so the table will not contain any row for salesman 'john' and product 'butter'
same way some other salesman may not have sales figure for some other product.
I want the output in matrix form.
colum wise --> products and
row wise ---> salesman
Butter Cream Powder
John 0 4 4
Smith 10 0 1
Paul 2 2 0
Please remember the number of products/salesman is not known, i.e. there may be 20 products , there may be 2 products.
AS the name/number of products is not known , so i can't directly use "decode".
SO how do i go about writting the query for the same.
In addition to it , it should show zero , where no sales figure is found for a paricualr salesman/product.
Please suggest.
Rajeev katyal

Answer 1

what is your collect function?
cant you simply do this?
SQL> with emp as (select 10 as deptno, 'king' as ename from dual union all
  2  select 10 as deptno, 'clark' as ename from dual union all
  3  select 10 as deptno, 'john' as ename from dual union all
  4  select 11 as deptno, 'scott' as ename from dual union all
  5  select 11 as deptno, 'michael' as ename from dual)
  6  select deptno,    max(sys_connect_by_path(ename, ' ' )) scbp
  7         from (select deptno, ename,
  8      row_number() over
  9                (partition by deptno order by ename) rn
10                                  from emp                  
11                      )     start with rn = 1
12                               connect by prior rn = rn-1                         
13                               and prior deptno = deptno                            
14                               group by deptno                               
15                               order by deptno;
    DEPTNO SCBP
        10  clark john king
        11  michael scott
SQL>