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Fatal error: Uncaught TypeError: pg_query(): Argument #1 ($connection) must be of type PgSql\Connection, null given in /home/jiphjxbn/dev/php/cronjobs/deleteTemporaryStudents.php:31 Stack trace: #0 /home/jiphjxbn/dev/php/cronjobs/deleteTemporaryStudents.php(31): pg_query(NULL, '\n SELECT...') #1 {main} thrown in /home/jiphjxbn/dev/php/cronjobs/deleteTemporaryStudents.php on line 31