如果不对列进行分组,如何获得正确的分组。查询得到错误的结果
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使用案例时,在分组时给出错误的结果。
CREATE TABLE inv
(invid int, co int4, type varchar(1), sum int4);
INSERT INTO inv
(invid, co, type, sum)
VALUES
(1, 1,'J',1000),
(2, 1,'O',2000),
(3, 2,'O',3000),
(4, 3,'J',4000),
(5, 4,'J',1000),
(6, 2,'O',2000),
(7, 1,'J',1000)
;
CREATE TABLE co
(coid int, name varchar(30));
INSERT INTO co
(coid, name)
VALUES
(1,'Volvo'),
(2,'BMW'),
(3,'Microsoft'),
(4,'Apple')
;
沃尔沃出现两次,因为发票有两种类型。
SELECT name,type,
CASE
WHEN type ='J' THEN 100
WHEN type ='O' THEN 200
ELSE 0 END AS cost,
sum(sum)
FROM inv
LEFT JOIN co ON coid=co
GROUP BY name,type
问题很简单:我如何只按公司分组?
我知道之前已经提出了类似的问题,但我找不到涉及案件的任何问题。
预期输出(不需要类型):
Volvo J 100 2000
Apple J 100 1000
Microsoft J 100 4000
BMW O 200 5000
Volvo O 200 2000
http://sqlfiddle.com/#!15/35c5df/5
TIA
答案 0 :(得分:3)
select
name,
sum ( case
when type = 'J' then 100
when type = 'O' then 200
else 0 end
) as cost,
sum("sum") as "sum"
from inv left join co on coid=co
group by name