SQL多重条件CASE WHEN和或

时间:2020-09-16 08:51:04

标签: sql-server tsql case

我加入了两个表(tbl1和tbl2)。两个表中都存在AnimalNo,但这是tbl1的主键,并且可以在tbl2中多次出现(如果AnimalNo与多个ConditionID相关联)

tbl1

AnimalNo  |   KillDate
1         |   01/01/2019
2         |   01/01/2019
3         |   01/01/2019
4         |   01/01/2020
5         |   01/01/2020

tbl2

AnimalNo  |   ConditionID
1         |   1
1         |   2
2         |   1
3         |   1
3         |   2 
4         |   1
5         |   1
5         |   2         

在上面的示例中,我想要一个表,该表中我得到具有每种条件的AnimalID的计数以及都具有AnimalNo 1和2的ConditionID的计数:

Year  |  N_killed   |  Type1   | Type2    | Both 
2019  |  3          | 3        | 2        |  2      
2020  |  2          | 2        | 1        |  1      

我有这个查询,可以成功告诉我每个单独的AnimalNo的{​​{1}}的数量,但是我想添加最后一个称为ConditionID的列,该列具有Both同时具有AnimalNo 1和2

ConditionID

2 个答案:

答案 0 :(得分:1)

我想这就是你想要的

SELECT
  
  DATEPART(year, tbl1.KillDate) AS KillYear,
                COUNT(Distinct tbl1.AnimalNo) AS N_Killed,
                COUNT(CASE WHEN tbl2.ConditionId =9 THEN 1 END) AS Type1a,
                COUNT(CASE WHEN tbl2.ConditionId =75 THEN 1 END) AS Type1b,
                COUNT(CASE WHEN tbl2.ConditionId =23 THEN 1 END) AS Type2a,
                COUNT(CASE WHEN tbl2.ConditionId =81 THEN 1 END) AS Type2b,
                COUNT(CASE WHEN tbl2.ConditionId IN (9,75) OR tbl2.ConditionId IN (23,81) BothTypes
FROM tbl1 LEFT JOIN
     tbl2 ON tbl1.AnimalNo = tbl2.AnimalNo
WHERE YEAR(tbl1.KillDate) >=2012
GROUP BY DATEPART(year, KillDate)
ORDER BY DATEPART(year, KillDate)

答案 1 :(得分:1)

尝试一下:

declare @tbl1 table
(
AnimalNo int
,KillDate date
)

insert into @tbl1(AnimalNo, KillDate)
select 1, '2019-01-01' union
select 2, '2019-01-01' union
select 3, '2019-01-01' union
select 4, '2020-01-01' union
select 5, '2020-01-01'

declare @tbl2 table
(
AnimalNo int
,ConditionID int
)

insert into @tbl2(AnimalNo, ConditionID)
select 1,1 union
select 1,2 union
select 2,1 union
select 3,1 union
select 3,2 union
select 4,1 union
select 5,1 union
select 5,2


select
year(k.KillDate) as [Year]
,count(distinct k.AnimalNo) as N_Killed
,sum(c.Type1)
,sum(c.Type2)
,sum(case when c.Type1 = 1 and c.Type2 = 1 then 1 else 0 end) as Both
from

@tbl1 k

JOIN
(
select 
c.AnimalNo
,max(case when c.ConditionID = 1 then 1 else 0 end) as Type1
,max(case when c.ConditionID = 2 then 1 else 0 end) as Type2
from
@tbl2 c
group by c.AnimalNo
) c
on k.AnimalNo = c.AnimalNo
group by year(k.KillDate)
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