RE: Simple Display file problem

From: Alan Campin

Also, on the question of position to SQL result couldn't you do a
subquery to return the mileage result and then select the result based
on a mileage range that is input?

You're mixing up examples.  With a logical file or an OPQNRYF, I can
position myself to different places in the index in response to user input.
For example, I can order all customer orders by date and then by customer,
and then position myself to the first order for a given date with a simple
SETLL.  If the user enters another date, I can position to that date with
another SETLL instantaneously.

There is no way to do that in SQL without running a new SELECT.  In fact,
the nearest thing you can do is to move your cursor "N" rows forward or
backward, but this is a very expensive operation on most databases. 

SQL does support what you want, just not the way you thinking about it.

No it doesn't.  And AFAIK, there is no plan for keyed positioning, even in
SQL3 (ANSI/ISO SQL 2003).

Joe