如何在 Oracle 数据库中的单个列中连接 case 语句值的值

Question

select
case
when s.X344731='Y' then 'Property Tax Assessment'
when s.X344732='Y' then 'Property Tax Payment'
when s.X344733='Y' then 'Birth and Death Certificate'
when s.X344734='Y' then ' Trade License'
when s.X344735='Y' then ' Complaints/Grievance Redressal'
when s.X344736='Y' then 'Water Connection'
when s.X344737='Y' then 'Sewerage Connection'
when s.X344738='Y' then 'Online Building Plan Approval System'    
when s.X344739='Y' then ' Fire NOC'    
when s.X3447310='Y' then ' NOC (Others)'    
when s.X3447311='Y' then 'Certificates (Others)'    
when s.X3447312='Y' then 'User Charges (water charges, parking fee, advertisement charges, electricity charges etc. )'    
when s.X3447313='Y' then 'All of the above'    
when s.X3447314='Y' then 'None of the above'    
else 'Not Answered' end as municipal_services_do_you_use    
from lime_survey_988773 s 
left join lime_tokens_988773 t 
on (s.token=t.token)     
where s.submitdate is not null 
and user_id=143561; 

我想将这三个"财产税评估"，"财产税支付"和"出生和死亡证明"的值连接起来，它将如下所示：

User_id  Municipal_Services_Do_you_use                                                      State
142351   ('Property Tax Assessment', 'Property Tax Payment','Birth and Death Certificate')  Delhi

Answer 1

您可以将条件聚合与串联运算符(||)

一起使用，例如

SELECT user_id AS "User_id",
MAX(CASE WHEN s.X344731='Y' THEN '(''Property Tax Assessment''' END)||
MAX(CASE WHEN s.X344732='Y' THEN ',''Property Tax Payment''' END)||
MAX(CASE WHEN s.X344732='Y' THEN ',''Birth and Death Certificate'')' END) 
AS "Municipal_Services_Do_you_use"     
FROM lime_survey_988773 s 
LEFT JOIN lime_tokens_988773 t 
ON t.token = s.token  
WHERE user_id = 143561 
GROUP BY user_id

将返回所需的结果，前提是在联接这些表后user_id = 143561，每列至少返回一个名称为X344...的'Y'值。