SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: SELECT t.* FROM bb1_threads t WHERE t.threadid = '185864'
mysql error: Out of resources when opening file './usr_web1_2/bb1_threads.MYD' (Errcode: 24)
mysql error number: 23
mysql version: 5.5.47-0+deb6u1-log
php version: 5.3.3-7+squeeze29
Date: 08.07.2020 @ 09:06
Script: /print.php?threadid=185864&page=1
Referer: