As discovered during T328224: Deploy PageAssessments to Nepali Wikipedia, with thanks to @TheDJ for discovering, a VARBINARY(20) is inadequate for storing localised article classes/importances in languages with multibyte scripts.
describe page_assessments; +------------------+------------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +------------------+------------------+------+-----+---------+-------+ | pa_page_id | int(10) unsigned | NO | PRI | NULL | | | pa_project_id | int(10) unsigned | NO | PRI | NULL | | | pa_class | varbinary(20) | YES | | NULL | | | pa_importance | varbinary(20) | YES | | NULL | | | pa_page_revision | int(10) unsigned | NO | | NULL | | +------------------+------------------+------+-----+---------+-------+ 5 rows in set (0.001 sec)
It is proposed that pa_class and pa_importance 's type is changed to VARBINARY(80)