update 전/후 데이터 반환받기

use test;

drop table if exists xxx_user;

create table xxx_user (

usn int not null auto_increment

, money int not null

, grade char(1) not null

, reg_date datetime

, primary key (usn)

) engine=innodb default charset=utf8mb4;

insert into xxx_user values (null, 1000, 'A', now()), (null, 2000, 'B', now()), (null, 3000, 'C', now());

select * from xxx_user;

set @uv_money_old := -999, @uv_money_new := -999;

select @uv_money_old, @uv_money_new;

select * from xxx_user where usn = 1;

update xxx_user

set money = (@uv_money_new := (@uv_money_old := money) - 50)

, grade = 'Z'

where usn = 1;

select * from xxx_user where usn = 1;

select @uv_money_old, @uv_money_new;