使用SUM检索2个表中的记录并获取最新记录

如何解决使用SUM检索2个表中的记录并获取最新记录

我有一个表名“ claims”和“ entries”。 Claims表是父级，条目是子级。我正在尝试获取索赔表中的最新条目。这是简化后的数据：

Claims Table
rID     code     dateOn
1        A      2/12/2020
2        B      1/23/2020
3        A      7/11/2020
4        A      8/20/2020

Entries Table
eID     rID    type     amount
1        1     cat        5
2        3     cat        5
3        4     dog        5
4        1     dog        5
5        1     cat        2

Desired Result
code   latestCatDate    latestDogDate    DogTotal    CatTotal
A         7/11/2020        8/20/2020        10          12

这是没有日期的我的SQL的样子...这很正常：

SELECT 
code,SUM(case when entries.type='cat' then entries.amount else 0.0 end),SUM(case when entries.type='dog' then entries.amount else 0.0 end),FROM claims c INNER JOIN entries ON entries.rID=c.rID

WHERE c.code='A'

GROUP BY code

我对如何获取LatestDogDate和LatestCatDate感到困惑。

解决方法

您可以简单地向查询中添加更多条件聚合表达式，如下所示：

SELECT 
    c.code,MAX(CASE WHEN e.type = 'cat' THEN dateOn end) latestCatDate,MAX(CASE WHEN e.type = 'dog' THEN dateOn end) latestDogDate,SUM(CASE WHEN e.type = 'cat' THEN e.amount else 0.0 end) catTotal,SUM(CASE WHEN e.type = 'dog' THEN e.amount else 0.0 end) dogTotal
FROM claims c 
INNER JOIN entries e ON e.rID = c.rID
WHERE c.code = 'A'
GROUP BY code

,

使用PIVOT和GROUP BY

with
Claims as (
    select * from (values
    (1,'A','2/12/2020'),(2,'B','1/23/2020'),(3,'7/11/2020'),(4,'8/20/2020')
    ) x (rID,code,dateOn)
),Entries as (
    select * from (values
    (1,1,'cat',5),3,4,'dog',(5,2)
    ) x (eID,rID,type,amount)
),j as (
    select c.*,e.type t2,e.eid,amount
    from Claims c
    join Entries e on c.rID = e.rID
),p1 as (
    select p.code,t2,max(p.dateon) d,sum(cat) tot_cat,sum(dog) tot_dog
    from j
    pivot ( sum(amount) for type in ([cat],[dog])) p
    group by p.code,t2
),p2 as (
    select *
    from p1
    pivot (max(d) for t2 in ([cat],[dog])) p
)
select max(code) code,max(tot_cat) tot_cat,max(tot_dog) tot_dog,max(cat) latestCatDate,max(dog) latestDogDate 
from p2