DB Error: unknown error

SELECT DISTINCT(p.pid), p.*, p2.pdate AS pdatex, date_format(p2.pdate, "%d.%m.%Y") AS pdate, time_format(p2.pdate, "%H:%i") AS ptime, a.alt_name as a_alt_name FROM cat3_product p INNER JOIN cat3_actors AS a ON p.actor = a.id RIGHT JOIN cat3_product p2 ON ((p2.pid=p.pid OR p2.parent=p.pid) AND p2.pdate >= NOW() ) WHERE p.parent = 0 AND p.active = 1 AND p.active = 1 AND (p.region = 1 OR p.is_global = 1) GROUP BY p.pid ORDER BY pdatex ASC LIMIT 0, 32 [nativecode=1 ** Can't create/write to file '/tmp/#sql_b44_2.MYI' (Errcode: 28)]

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