Discuz! info: MySQL Query Error

Time: 2018-9-20 8:30pm
Script: /index.php

SQL: SELECT * FROM cdb_crons WHERE available>'0' AND nextrun<='1537446629' LIMIT 1
Error: Table 'amsforum_forumdb.cdb_crons' doesn't exist
Errno.: 1146

Similar error report has beed dispatched to administrator before.