This may be something I need to sleep on, but I'd be grateful for some tips.

I need to create a delivery list, which I can maintain in order, and
insert and move individual entries ("before" and "after"). There are a
number of individual "runs", which should be separate, thus...

SELECT DELIVERYID, RUNORDER FROM RUNTABLE WHERE DRIVERID = x ORDER BY
RUNORDER ASC.

The question is, let's say I want to move deliveryid x to another place
in the runorder? How can I do that and "bump up" any existing deliveries
above it so that when I run the query again it's in the right place?

Any thoughts for the structure or queries would be gratefully received,