I think I will probably have to add some extra logic into this problem,
but it SHOULD be simple enough ...

Table with three fields - Gallery_No, Image_No, Item_position

A gallery can consist of any number of images but we normally only
display a selection of up to 30. Item_position is a FLOAT which allows
several styles ordering, with one style 'page.pos' so one can group
pictures to a variable length page. The bottom line here is that
'Item_position' is not sequential ... and that is the rub. I now need to
identify the record before and the record after for a library system
where each gallery is a collection of pdf articles and the client would
like to be able to navigate back and forward through each volume.

In the past ( 20 years ago ;) ) I would simply have added a second
position column which is consecutive numbers and reordered them when
changes are made, but I'm wondering if with all the things that have
been added since then has provided an SQL means of returning the before
and after value directly from the current data?

--
Lester Caine - G8HFL
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