Question

我在 SQLite ：

中编写了以下代码

CREATE TABLE payments (
  customerNumber REAL NOT NULL,
  checkNumber TEXT NOT NULL,
  paymentDate TEXT NOT NULL,
  amount REAL NOT NULL,
  rank REAL default 0,
  PRIMARY KEY  (customerNumber,checkNumber)
);

insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(103,'HQ336336','2004-10-19 00:00:00',6066.78);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(103,'JM555205','2003-06-05 00:00:00',14571.44);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(112,'BO864823','2004-12-17 00:00:00',14191.12);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(112,'HQ55022','2003-06-06 00:00:00',32641.98);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(121,'MA302151','2004-11-28 00:00:00',34638.14);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(121,'KI831359','2004-11-04 00:00:00',17876.32);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(161,'KG644125','2005-02-02 00:00:00',12692.19);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(161,'NI908214','2003-08-05 00:00:00',38675.13);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(181,'CM564612','2004-04-25 00:00:00',22602.36);
insert  into payments(customerNumber,checkNumber,paymentDate,amount) values(181,'GQ132144','2003-01-30 00:00:00',5494.78);

现在我的问题是，如何根据“按客户编号从付款组中总计（金额）”的排名来更新表格中的排名列？

Answer 1

编辑（删除了SQL Server代码，SQLite不支持更新语句中的联接）：

我认为这应该没问题：

drop table if exists ranks;

create temp table ranks (
    rank integer primary key,
    customerNumber real,
    total real
);

insert into ranks
select null, customerNumber, total(amount) as total
from payments
group by customerNumber
order by total desc;


update payments set
    rank = (
        select rank from ranks 
        where customerNumber = payments.customerNumber
    );

select * from payments;

<强>加了：

这是一个非常非常脏的方法，在一个语句中执行它，它使用非常特定的子查询来排名（它是某种SQLite行号）每个客户。正如我所说的，许多sybqueries，但这是使它在一个查询中工作而不使用join in update的代价。

update payments set
    rank = (
        select
            (select count(0) from (select total(amount) as t, customerNumber as c
                    from payments group by customerNumber order by t desc) t1
            where t1.t >= t2.t) as rank
        from (select total(amount) as t, customerNumber as c from payments group by customerNumber order by t desc) 
        t2 where t2.c = payments.customerNumber order by t2.t desc
    );

根据组的总数更新排名列

1 个答案: