buff3.0/backend-admin/migrations/20260411_add_cards_remark.sql

-- 卡密备注（管理员可见）
ALTER TABLE `cards`
  ADD COLUMN `remark` VARCHAR(500) NULL DEFAULT NULL COMMENT '备注' AFTER `is_gift`;

ALTER TABLE `cards_his`
  ADD COLUMN `remark` VARCHAR(500) NULL DEFAULT NULL COMMENT '备注' AFTER `is_gift`;