Getting row before and after a query

Question

I currently have this query

SELECT  short_url,
        type,
        file_thumbnail,
        file_embed,
        media.id,
        user,
        media.file_u         


        

Answer 1

Do you really want the next row in the database? Is you data indexed on info.id? If not your next row might not be the item you expect. What do you do if you need to change the order of items?

You could consider having next_id and previous_id as fields on info, and then

SELECT
    ...
FROM info current_info
INNER JOIN media current_media
    ON current_info.id = current_media.id

INNER JOIN info prev_info
    ON prev_info.id = current_info.previous_id 
INNER JOIN media prev_media
    ON prev_info.id = prev_media.id

INNER JOIN info next_info
    ON next_info.id = current_info.next_id 
INNER JOIN media next_media
    ON next_info.id = next_media.id

WHERE current_media.id = '$id'

This has the advantages of always returning a single row. Why is that good? If there is no previous or no next how do you tell if your two returned rows are previous and current, or current and next.

It is also more manageable as you can reorder items by changing their sibling ids.

(WARNING: the code above may not work, i have no sql client on my laptop. But hopefully it will point you in a good direction)