-- 应收日志兼容余额核销：仅更新字段注释，不改变字段类型和历史数据
ALTER TABLE ar_bill_log
  MODIFY COLUMN object_type VARCHAR(40) NOT NULL
    COMMENT 'BILL/RECEIPT/WRITEOFF/EXPORT/BALANCE_WRITEOFF',
  MODIFY COLUMN operation_type VARCHAR(40) NOT NULL
    COMMENT '操作类型：CONFIRM/VOID/EXPORT/RECEIPT/CANCEL_RECEIPT/WRITEOFF/CANCEL_WRITEOFF/BALANCE_WRITEOFF/CANCEL_BALANCE_WRITEOFF';