SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: UPDATE bb1_guthaben_bank SET akt_jahr='2023', crashtag='301', boersencrash='0',boersencrashdate = '', boersencrashaktienwert='', boersencrashprozent='',boersencrashaktienwertneu='' WHERE bankid='1'
mysql error: Incorrect integer value: '' for column `web8_corelith_db`.`bb1_guthaben_bank`.`boersencrashaktienwert` at row 1
mysql error number: 1366
mysql version: 10.5.19-MariaDB-0+deb11u2
php version: 5.6.40
Date: 10.06.2023 @ 18:54
Script: /hmportal.php
Referer: