Dynamic date parameters for a scheduled report that runs every day

Question

I have a report that has input parameters for a start date and
end date. The report will be scheduled to run once a day at a
scheduled time. I need the report to automatically set the start
date and end dates when the report runs at the scheduled time.
When the report runs at the scheduled time, the end date needs
to be set to that time and the start date needs to be set to 24
hrs before the end date. I want the start and end dates to roll
forward automatically when the scheduled report runs each day. I
don't want any user intervention to change the start and end
dates every day. How can I do this in a report ?
Also, since the report is scheduled to run each day, I want the
output to be saved to a unique file name each time the report is
run as each day's report will report on the data only for that
day. How can I get the report to save to a unique file name
automatically each day ? Again, I don't want any user
intervention where they would set the output file name manually.

Answer 1

Try adding the following in the beforereport or beforepform
trigger, before the RETURN clause (TRUNC gets rid of the time
component of the date):
:p_date_from := TRUNC(sysdate) - 1;
:p_date_to := TRUNC(sysdate);
:desname := 'REPORT'||TO_CHAR(sysdate, 'DDMMYYYY')||'.txt'
Paul Williams