Comparando fechas

[ayabass]

Me han dado la soluccion:

SELECT t2.* FROM (SELECT t1.fecha, t1.diferencia as dif, t1.ord2 FROM ((SELECT fecha, DATEDIFF(CURDATE(),fecha) diferencia, 'ant' ord2 FROM `tabla` where fecha < CURDATE() ORDER BY fecha DESC limit 4 )
UNION ALL
(SELECT fecha,DATEDIFF(fecha,CURDATE()), 'post' FROM `tabla` where fecha > CURDATE() order by fecha ASC limit 4))t1 ORDER BY t1.diferencia, ord2 LIMIT 4)t2 ORDER BY t2.fecha

Gracias!!