ALTER TABLE `t_meetingroom`
MODIFY COLUMN `pic` varchar(8000) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '会议室图片' AFTER `capacity`;

ALTER TABLE `t_meetingroom_book`
MODIFY COLUMN `matter` varchar(8000) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT '使用事项' AFTER `dept`;