MySQL error in file: /engine/modules/functions.php at line 736

Error Number: 126

The Error returned was:
Incorrect key file for table '/tmp/#sql_4d44_0.MYI'; try to repair it

SQL query:

SELECT p.id, p.autor, p.date, p.short_story, CHAR_LENGTH(p.full_story) as full_story, p.xfields, p.title, p.category, p.alt_name, p.comm_num, p.allow_comm, p.fixed, p.tags, e.news_read, e.allow_rate, e.rating, e.vote_num, e.votes, e.view_edit, e.editdate, e.editor, e.reason FROM dle_post p LEFT JOIN dle_post_extras e ON (p.id=e.news_id) WHERE category regexp '[[:<:]](1|2|3|4|5|6|7|8|9|10|11|12|13|14|15|16|17|18|19|20|45|47|48|49|50|51|52)[[:>:]]' AND approve=1 AND date < '2018-09-19 22:30:42' ORDER BY RAND() LIMIT 0,6