-- Tables affected: qt_configurations
-- recovery.not-started: safe to re-run; ADD COLUMN IF NOT EXISTS
-- recovery.partial: ALTER TABLE qt_configurations DROP COLUMN support_code;
-- recovery.completed: no action needed
-- verify: support_code column missing | SELECT 1 FROM information_schema.COLUMNS WHERE table_schema=DATABASE() AND table_name='qt_configurations' AND column_name='support_code' HAVING COUNT(*)=0

ALTER TABLE qt_configurations
    ADD COLUMN IF NOT EXISTS support_code VARCHAR(20) NULL AFTER server_model;