Discuz! info: MySQL Query Error

Time: 2017-11-18 11:43pm
Script: /index.php

SQL: SELECT * FROM [Table]settings WHERE variable NOT IN ('siteuniqueid', 'mastermobile', 'bbrules', 'bbrulestxt', 'closedreason', 'creditsnotify', 'backupdir', 'custombackup', 'jswizard', 'maxonlines', 'modreasons', 'newsletter', 'welcomemsg', 'welcomemsgtxt', 'postno', 'postnocustom', 'customauthorinfo') AND SUBSTRING(variable, 1, 9)<>'jswizard_'
Error: No database selected
Errno.: 1046

Similar error report has beed dispatched to administrator before.