【SQL33】求付款最早和最小付款的信息

有如下一張表Orders

id    pdate             payno
1     2019-11-02        5
1     2019-11-02        3
1     2019-11-03        1
1     2019-11-03        3
2     2019-11-09        1
2     2019-11-09        4
2     2019-11-08        3
2     2019-11-08        2

查詢出每個發貨單號(shipid)，最早付款時間(paydate)和最小付款單號(payno)

結果如下：

id    pdate             payno
1     2019-11-02        3
2     2019-11-08        2

解決：

select id
      ,pdate
      ,payno
  from (
        select id
              ,pdate
              ,payno
              ,rownumber() over(partition by id,pdate order by payno) as rn
          from orders
        )a
 where rn = 1
;

id	pdate	payno
1	2019-11-02	3
2	2019-11-08	2

備註：建表和數據
create table orders(id int,pdate date,payno int);
insert into orders values(1,'2019-11-02',5);
insert into orders values(1,'2019-11-02',3);
insert into orders values(1,'2019-11-03',1);
insert into orders values(1,'2019-11-03',3);
insert into orders values(2,'2019-11-09',1);
insert into orders values(2,'2019-11-09',4);
insert into orders values(2,'2019-11-08',3);
insert into orders values(2,'2019-11-08',2);