Drillthrough parameters

I've set a report that drills through to another report.
There is a parameter on the second report (sales orders)
called 'order_no'.
I can set up the drill through so clicking on an order
number on the first report links to the sales order
report, with the appropriate order number selected. What I
would like to be able to do is populate the parameter
values list from a query, so once the user has drilled-
through, they can browse through other sales orders using
the paramater.
Assuming the order_no parameter '000118' is sent through
to the sales orders report, I can display the correct
sales order. However, if I populate the paramater from a
query, I lose that value. Ideally I would like the default
parameter value to be the one passed from the first
report, but of course, you cannot set a parameter to
itself. Should I pass a second parameter to use for
setting the default value? It doesn't seem like a logical
way of doing things.
I hope this makes sense, and that someone can shed some
light on the issue.
Thanks,
Chris Ashworth.Chris,
I hope you don't mind if I piggy-back onto your inquiry. I'm looking for an
answer as well. I have several drill down reports where I'd like the user to
be able to see the parameter dropdowns, but have noticed that when a report
is drilled to, the parameters no longer show. Is there any kind of toggle to
show parameters, even after a drill down?