Question

我想在两个计数器上测试2个条件。样本：

@verifier = ActiveSupport::MessageVerifier.new('s3Krit')
cookies[:remember_me] = @verifier.generate([@user.id, 2.weeks.from_now])
id, time = @verifier.verify(cookies[:remember_me])

我＆＃39;预计会有

 id_client | zipcode     | timestamp               | UC     | MISS
--------------------------------------------------|--------|------
amar      | 11111       | 2016-09-28 20:05:03.001 | 15     | 0
akbar     | 11111       | 2016-09-28 20:05:03.001 | 50     | 1  
antony    | 11111       | 2016-09-28 20:07:03.001 | 110    | 0
amar      | 11111       | 2016-09-28 20:08:03.001 | 5      | 1

select
  date (CollectionTime) as dates,
  id_client
  case when UC <=15 THEN 'TB'
    UC < 15 THEN 'TB'
    UC > 15  AND UC <=40 THEN 'B'
    UC >40  AND  UC <=80 THEN 'M'
    UC > 80 THEN 'TM'
    ELSE 'NULL' END AS tranche_UC
  case when MISS = O THEN 'BONNE'
  MISS =1 THEN 'Mauvaise'
  ELSE 'NULL' END AS note
from cm_stat 
group by id_client
order by dates;

Answer 1

您的查询建议您希望最后一列为bonne或mauvais而不是1或0，如示例所示。我会选择bonne和mauvais。

首先你有一些语法错误：

在id_client
WHEN

CASE

这是没有语法错误的查询：

select
  date (CollectionTime) as dates,
  id_client, -- missing comma
  case
    when UC <=15 THEN 'TB'
    when UC < 15 THEN 'TB' -- needed WHEN (use before every condition)
    when UC > 15  AND UC <=40 THEN 'B' -- needed WHEN
    when UC >40  AND  UC <=80 THEN 'M' -- needed WHEN
    when UC > 80 THEN 'TM' -- needed WHEN
    ELSE 'NULL' END AS tranche_UC
  case
    when MISS = O THEN 'BONNE'
    when MISS =1 THEN 'Mauvaise' -- needed WHEN
    ELSE 'NULL' END AS note
from cm_stat 
group by id_client
order by dates;

现在语法已全部设置，您有一些逻辑错误：

UC逻辑过度（例如，检查＆lt; = 15 和＆lt; 15以返回TB）
我不明白为什么你有group by id_client

所以这里是逻辑理顺的查询：

select
  date (CollectionTime) as dates,
  id_client,
  case
    when UC <=15 THEN 'TB'
    when UC <=40 THEN 'B'
    when UC <=80 THEN 'M'
    when UC > 80 THEN 'TM'
    ELSE 'NULL' END AS tranche_UC
  case
    when MISS = O THEN 'BONNE'
    when MISS = 1 THEN 'Mauvaise'
    ELSE 'NULL' END AS note
from cm_stat
order by dates;

SQL：条件测试

1 个答案: