How to display week number in a report

Question

Hi,
I need to show the week number in a report and related sales data for that week. For example, starting from 01-JUL-2009 the week1 should show total of sales from 01-JUL-08-JUL.
Help please....
Thanks
A/A

Answer 1

If you are trying to extract the week number of the calender year...you can use..
sql> select to_char(sysdate,'WW') from dual;
TO
05and then group the sales figures by week...
sql> create table t(
  2     target_date date,
  3     sales       number);
Table created.
sql> begin
  2     for i in 1..30 loop
  3        insert into t values (sysdate-i,100*i);
  4     end loop;
  5   commit;
  6  end;
  7  /
PL/SQL procedure successfully completed.
sql> select week, sum(sales) from (
  2     select sales, to_char(target_date,'WW') week from t)
  3   group by week;
WE SUM(SALES)
05       2100
02      16800
01       8800
04       7000
03      11900However, if your week calculation starts with a particular date like a calender year starting with 01-june-2010, then you would need to calculate the (relative) week number using something like...
  1  select target_date,
  2         trunc(((target_date - to_date('01-june-2010','DD-MON-YYYY'))/7)) week_number
  3*   from t
sql> /In the above code, 01-june-2010 is the date from which my calender year starts.
Please note that since this is relative, you might get negative numbers for weeks.