Select the next row below:
SELECT * FROM Example WHERE id < 3 ORDER BY id DESC LIMIT 1
Select the next row above:
SELECT * FROM Example WHERE id > 3 ORDER BY id LIMIT 1
Select both in one query, e.g. use UNION:
(SELECT * FROM Example WHERE id < 3 ORDER BY id DESC LIMIT 1)
UNION
(SELECT * FROM Example WHERE id > 3 ORDER BY id LIMIT 1)
That what you mean?