SQL LISTAGG 查询未创建连接字符串答案

【问题标题】：SQL LISTAGG query is not creating a concatenated stringSQL LISTAGG 查询未创建连接字符串
【发布时间】：2019-02-13 21:20:18
【问题描述】：

我正在尝试使用 Oracle LISTAGG 创建基于行的串联值字符串。这是仍然显示我正在尝试解决的问题的简化代码。

SELECT S_SUBJECT.UNIQRECNUM,                      
(SELECT LISTAGG(S_STUDY.U_PRIMARYRESEARCHCOHORT,',') WITHIN GROUP ( 
     ORDER BY U_PRIMARYRESEARCHCOHORT)
     FROM S_STUDY
     WHERE S_STUDY.S_STUDYID = S_PARTICIPANT.SSTUDYID) COHORTS

FROM S_SUBJECT
JOIN S_PARTICIPANT ON S_PARTICIPANT.SUBJECTID = S_SUBJECT.S_SUBJECTID
WHERE S_SUBJECT.UNIQRECNUM IN ('9','8','7','6','5','2');


These are the results of this query;
UNIQRECNUM | COHORTS
---------------------
    2      | Gastro
    5      | Metabolic
    6      | Cardio
    7      | Cardio
    8      | Gastro
    8      | Cardio
    9      | Gastro
    9      | Gastro
    9      | Gastro


What I am expecting to see from LISTAGG would be
UNIQRECNUM  | COHORTS
--------------------
    2       | Gastro
    5       | Metabolic
    6       | Cardio
    7       | Cardio
    8       | Cardio,Gastro
    8       | Cardio,Gastro
    9       | Gastro,Gastro,Gastro
    9       | Gastro,Gastro,Gastro
    9       | Gastro,Gastro,Gastro

【问题讨论】：

标签： sql oracle listagg

【解决方案1】：

我相信您的查询会是这样的：

SELECT S_SUBJECT.UNIQRECNUM,                      
  LISTAGG(S_STUDY.U_PRIMARYRESEARCHCOHORT,',') WITHIN GROUP ( 
     ORDER BY U_PRIMARYRESEARCHCOHORT) COHORTS
FROM S_SUBJECT
JOIN S_PARTICIPANT ON S_PARTICIPANT.SUBJECTID = S_SUBJECT.S_SUBJECTID
JOIN S_STUDY ON S_STUDY.S_STUDYID = S_PARTICIPANT.SSTUDYID
WHERE S_SUBJECT.UNIQRECNUM IN ('9','8','7','6','5','2')
GROUP BY S_SUBJECT.UNIQRECNUM;

【讨论】：

【解决方案2】：

为什么不

select u.uniqrecnum,
  listagg(t.u_primarysearchcohort, ',') 
    within group (order by t.u_primarysearchcohort) cohorts
from s_subject u join s_study t on t.s_studyid = p.sstudyid
join s_participant p on p.subjectid = u.s_subjectid
where u.uniqrecnum in ('9','8','7','6','5','2')
group by u.uniqrecnum;

【讨论】：

【解决方案3】：

试试这个：

样本数据：

UNIQRECNUM COHORTS  
---------- ---------
         2 Metabolic
         5 Cardio   
         6 Cardio   
         7 Gastro   
         8 Gastro   
         8 Cardio   
         9 Gastro   
         9 Gastro   
         9 Gastro   

WITH T AS 
(
    SELECT 2 AS  UNIQRECNUM,'Metabolic' AS COHORTS FROM DUAL
    UNION ALL
    SELECT 5 AS  UNIQRECNUM,'Cardio' AS COHORTS FROM DUAL
    UNION ALL
    SELECT 6 AS  UNIQRECNUM,'Cardio' AS COHORTS FROM DUAL
    UNION ALL
    SELECT 7 AS  UNIQRECNUM,'Gastro' AS COHORTS FROM DUAL
    UNION ALL
    SELECT 8 AS  UNIQRECNUM,'Gastro' AS COHORTS FROM DUAL
    UNION ALL
    SELECT 8 AS  UNIQRECNUM,'Cardio' AS COHORTS FROM DUAL
    UNION ALL
    SELECT 9 AS  UNIQRECNUM,'Gastro' AS COHORTS FROM DUAL
    UNION ALL
    SELECT 9 AS  UNIQRECNUM,'Gastro' AS COHORTS FROM DUAL
    UNION ALL
    SELECT 9 AS  UNIQRECNUM,'Gastro' AS COHORTS FROM DUAL
)
SELECT UNIQRECNUM,
     LISTAGG(COHORTS,',') WITHIN GROUP ( 
     ORDER BY COHORTS) OVER (PARTITION BY UNIQRECNUM) AS COHORTS 
FROM T;

输出：

UNIQRECNUM COHORTS                                                                                             
---------- ----------------------
         2 Metabolic                                                                                           
         5 Cardio                                                                                              
         6 Cardio                                                                                              
         7 Gastro                                                                                              
         8 Cardio,Gastro                                                                                       
         8 Cardio,Gastro                                                                                       
         9 Gastro,Gastro,Gastro                                                                                
         9 Gastro,Gastro,Gastro                                                                                
         9 Gastro,Gastro,Gastro

【讨论】：

【解决方案4】：

我想你想要一个窗口函数：

SELECT su.UNIQRECNUM,                      
       LISTAGG(st.U_PRIMARYRESEARCHCOHORT, ',') WITHIN GROUP
                   (ORDER BY U_PRIMARYRESEARCHCOHORT) OVER (PARTITION BY su.UNIQRECNUM) as COHORTS
FROM S_SUBJECT su JOIN
     S_PARTICIPANT p
     ON p.SUBJECTID = su.S_SUBJECTID JOIN
     S_STUDY st
     ON st.S_STUDYID = p.SSTUDYID
WHERE su.UNIQRECNUM IN ('9', '8', '7', '6', '5', '2');

【讨论】：

更正：（1）将分区拼写为分区（2）在更正这些错误后，s.UNIQRECNUM 应该是 su.UNIQRECNUM 我仍然遇到错误。 ORA-00904: "S_STUDY"."U_PRIMARYRESEARCHCOHORT": 标识符无效我检查了表，列存在并且拼写正确。