Howto only select secific lines from a result?

Hi,

I am working on a graphical table display widget which should be able
to display huge amounts of data, by lazy-loading database values. It
already works well if the primary-key and line-number are equal.
However I don't have any idea howto handle the case where the
primary-key contains holes, caused e.g. by deleting a few entries.

What I would need is a LIMIT command, which allows to LIMIT the
results in two ways.
Is there some way to select only specific lines from a result, something like:
Select * from table Where RESULNR BETWEEN 1000 and 1040?

Or do you have any other ideas howto solve this problem?

Thank you in advance, Clemens