根据 select 在另一个 table 上的结果更新 table

Question

我有两个这样的 table：

人：

id | name | sale | commission
1  | abc  | 0    |   0
2  | xyz  | 0    |   0

销售：

id | date       | person_id | sale | commission
1  | 2016-05-01 |     1     | 10   |     1
2  | 2016-05-02 |     1     | 10   |     1
3  | 2016-05-03 |     1     | 10   |     1
4  | 2016-05-01 |     2     | 20   |     2
5  | 2016-05-02 |     2     | 20   |     2
6  | 2016-05-01 |     2     | 20   |     2

我想用单个更新查询更新人 table 并将 table 更改为如下内容：

人：

id | name | sale | commission
1  | abc  | 30   |   3
2  | xyz  | 60   |   6

我知道我可以像下面这样总结销售但是如何将下面的查询结果直接更新为人table。

SELECT person_id, SUM(sale), SUM(commission) 
FROM sale
GROUP BY person_id;

Answer 1

 UPDATE person
 SET sale = (
    SELECT SUM(s.sale) FROM sale s
    WHERE s.person_id = person.id
 );

适合我。在以下位置查看实际效果：http://ideone.com/F32oUU

编辑具有附加聚合列的新版本：

UPDATE person SET 
 sale = (
    SELECT SUM(s.sale) FROM sale s
    WHERE s.person_id = person.id
 ),
 commission = (
    SELECT SUM(s.commission) FROM sale s
    WHERE s.person_id = person.id
 );

http://ideone.com/yo1A9Y

话虽如此，我确信 JOIN 解决方案更好，希望其他回答者能够 post 这样的解决方案。

Answer 2

正如 Strawberry 在您的问题下的评论中所说，在保存此信息之前请三思而后行。它被非规范化，变得陈旧。相反，请考虑在报告生成期间使用它。否则，如前所述，您可能运行会遇到问题。

drop table if exists person;
create table person
(   personId int auto_increment primary key,
    name varchar(100) not null,
    totSales decimal(9,2) not null,
    totComm decimal(9,2)
);
insert person(name,totSales,totComm) values
('Joe',0,0),
('Sally',0,0);
-- just added persons 1 and 2 (auto_inc)

drop table if exists sale;
create table sale
(   saleId int auto_increment primary key,
    saleDate date not null,
    personId int not null,
    sale decimal(9,2) not null,
    commission decimal(9,2) not null,
    index(personId), -- facilitate a snappier "group by" later
    foreign key (personId) references person(personId) -- Ref Integrity
);

insert sale(saleDate,personId,sale,commission) values
('2016-05-01',2,10,1),
('2016-05-01',1,40,4),
('2016-05-02',1,30,3),
('2016-05-07',2,10,1),
('2016-05-07',2,90,9);

-- the following dies on referential integrity, FK, error 1452 as expected
insert sale(saleDate,personId,sale,commission) values ('2016-05-01',4,10,1);

更新语句

update person p 
join  
(   select personId,sum(sale) totSales, sum(commission) totComm 
    from sale 
    group by personId 
) xDerived 
on xDerived.personId=p.personId 
set p.totSales=xDerived.totSales,p.totComm=xDerived.totComm;

结果

select * from person;
+----------+-------+----------+---------+
| personId | name  | totSales | totComm |
+----------+-------+----------+---------+
|        1 | Joe   |    70.00 |    7.00 |
|        2 | Sally |   110.00 |   11.00 |
+----------+-------+----------+---------+
2 rows in set (0.00 sec)

xDerived 只是一个别名。所有派生表都需要一个别名，无论您是否明确使用别名。

根据 select 在另一个 table 上的结果更新 table

Update table based on result of select on another table

mysql

bulk

updates

bulkupdate

更新语句

结果