事务

begin;
insert into products values(100,'p1',52);
insert into products values(101,'p2',36);
insert into orders values(9001,'上海');
insert into orders values(9002,'北京');
insert into order_items values(100,9001,10);
insert into order_items values(101,9002,30);
commit;

事务执行时，发生错误

commit后，重新执行就ok了，很奇怪。原因还不是很清楚，猜测是上个查询事务没有提交。