create database day0401_db;
use day0401_db;
create table tb_account(
name varchar(32),
money int
);
insert into tb_account values('a', 1000);
insert into tb_account values('b', 1000);
update tb_account set money=money-100 where name='a';
update tb_account set money=money+100 where name='b';
update tb_account set money=money-100 where name='a';
update tb_account set money=money+100 where name='b';
update tb_account set money=1000;
start transaction;
update tb_account set money=money-100 where name='a';
update tb_account set money=money+100 where name='b';
select * from tb_account;
rollback;
select * from tb_account;
start transaction;
update tb_account set money=money-100 where name='a';
update tb_account set money=money+100 where name='b';
select * from tb_account;
commit;
select * from tb_account;