MySQL error in file: /engine/classes/comments.class.php at line 815

Error Number: 1021

The Error returned was:
Disk full (/tmp/#sql-temptable-109051-d59c8-9d4d.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")

SQL query:

SELECT cm.id, cm.post_id, cm.user_id, cm.date, cm.autor as gast_name, cm.email as gast_email, text, ip, is_register, cm.rating, cm.vote_num, name, u.email, news_num, u.comm_num, user_group, lastdate, reg_date, signature, foto, fullname, land, u.xfields, p.title, p.date as newsdate, p.alt_name, p.category, p.allow_comm FROM dle_comments cm LEFT JOIN dle_post p ON cm.post_id=p.id INNER JOIN (SELECT DISTINCT(dle_post_extras_cats.news_id) FROM dle_post_extras_cats WHERE cat_id IN ('1','2','3','4','5','6','7','8','9','10','11','12','13','14','15','16','17','18','19','20','21','22','23','24','25','26','27','28','29','30','31','32','33','34','35','36','37','38','39','40','41','42','43','44','45','46','47','48','49','50','51','52','53','54','55','56','57','58','59','60','61','62','63','64','65','66','67','68','69','70','71','72','73','74')) c ON (p.id=c.news_id) LEFT JOIN dle_users u ON cm.user_id=u.user_id WHERE cm.approve=1 ORDER BY RAND() LIMIT 0,10