Question

谢谢，我在这个论坛上得到了慷慨的人们的大力帮助。我是Oracle SQL的初学者。

我在两个VIEW之间有一对多的关系，即PERSON_VIEW和PHONE_VIEW。在帮助下，我得到一个查询case /何时让手机工作，但当我将它添加回我的主查询时，它影响了我与TASK_VIEW的其他联接。

我想我需要将其添加为内部查询，所以我得到了一个结果。我在我的查询中添加了以下内容。我在TOAD中运行了查询，它给了我一个错误，“ORA-00979：不是GROUP BY表达式”，并突出显示了查询中的所有PERSON_ID。如果我采取以下左连接，它运行正常，不输出电话号码。任何帮助表示赞赏。

我还注意到，由于我带回了3个电话号码（小区，家庭和商业），因此从TASK返回时会导致重复。使用Task Inner Join，我得到了像

这样的结果

在： 1 John M. Doe ToDo1：ToDO1，ToDo2：ToDo2

在： 1 John M. Doe ToDo1：ToDO1，ToDo1：ToDO1，ToDo1：ToDO1，ToDo2：ToDo2，ToDo2：ToDo2，ToDo2：ToDo2

我从3个case语句中取出了最大值并运行了查询。但它为每个电话号码返回一个单独的行，如此

1 John Doe 999-999-9999 1 John Doe 888-888-8888 1 John Doe 222-222-2222

我该如何解决这个问题？

LEFT JOIN (SELECT PERSON_ID, PHONE_TP_SHORT_DESC,
                  max(case when PHONE_TYPE = 'HOME' then PHONE_NUMBER end) as HOME_PHONE,
                  max(case when PHONE_TYPE = 'BUSINESS' then PHONE_NUMBER end) as BUSINESS_PHONE,      
                  max(case when PHONE_TYPE = 'CELL' then PHONE_NUMBER end) as CELL_PHONE 
           FROM PHONE_VIEW) PHONE
ON PERSON.PERSON_ID = PHONE.PERSON_ID AND PHONE.PHONE_TYPE IN ('HOME','BUSINESS','CELL')

这是我正在尝试调试的整个查询

SELECT PERSON.PERSON_ID, 
       PERSON.FIRST_NAME,
       PERSON.MIDDLE_NAME,
       PERSON.LAST_NAME,
       PERSON.USER_NAME,
       PHONE.HOME_PHONE,
       PHONE.BUSINESS_PHONE,
       PHONE.CELL_PHONE,

LISTAGG(case  
        when SKILLS.SKILL_SHORT_DESC = 'ToDo1' then 'ToDo1:ToDo1'
        when SKILLS.SKILL_SHORT_DESC = 'ToDo2' then 'ToDo2:ToDo2'
        when SKILLS.SKILL_SHORT_DESC = 'ToDo3' then 'ToDo3:ToDo3'
        when SKILLS.SKILL_SHORT_DESC = 'ToDo4' then 'ToDo4:ToDo4'
        when SKILLS.SKILL_SHORT_DESC = 'ToDo5' then 'ToDo5:ToDo5'
        when SKILLS.SKILL_SHORT_DESC = 'ToDo6' then 'ToDo6:ToDo6'
      else ''

 end, ',')  
WITHIN GROUP (ORDER BY TASK.TASK_DESC )  AS TASK

FROM PERSON_VIEW PERSON

LEFT JOIN (SELECT PERSON_ID, PHONE_TP_SHORT_DESC,
                  max(case when PHONE_TYPE = 'HOME' then PHONE_NUMBER end) as HOME_PHONE,
                  max(case when PHONE_TYPE = 'BUSINESS' then PHONE_NUMBER end) as BUSINESS_PHONE,      
                  max(case when PHONE_TYPE = 'CELL' then PHONE_NUMBER end) as CELL_PHONE 
           FROM PHONE_VIEW) PHONE
ON PERSON.PERSON_ID = PHONE.PERSON_ID AND PHONE.PHONE_TYPE IN ('HOME','BUSINESS','CELL')                  


LEFT JOIN (SELECT DISTINCT PERSON_ID, TASK_DESC FROM TASK_VIEW) SKILLS
ON SKILLS.PERSON_ID = PERSON.PERSON_ID


GROUP BY 
PERSON.PERSON_ID,
PERSON.FIRST_NAME,
PERSON.MIDDLE_NAME, 
PERSON.LAST_NAME,
PERSON.USER_NAME,
PHONE.HOME_PHONE,
PHONE.BUSINESS_PHONE,
PHONE.CELL_PHONE

Answer 1

我确实发现您的查询存在一个问题。您对以下子查询有一个LEFT JOIN：

(SELECT PERSON_ID,
        PHONE_TP_SHORT_DESC,
        max(case when PHONE_TYPE = 'HOME' then PHONE_NUMBER end) as HOME_PHONE,
        max(case when PHONE_TYPE = 'BUSINESS' then PHONE_NUMBER end) as BUSINESS_PHONE,      
        max(case when PHONE_TYPE = 'CELL' then PHONE_NUMBER end) as CELL_PHONE 
 FROM PHONE_VIEW) PHONE

但是，在ON条件下，您会引用名为PHONE_TYPE的列：

ON PERSON.PERSON_ID = PHONE.PERSON_ID AND
   PHONE.PHONE_TYPE IN ('HOME','BUSINESS','CELL')

没有名为PHONE_TYPE的列可用，因此我预计会出现错误。有时，您从数据库（或编译器）获得的错误消息可能会产生误导，因为它并不总是揭示问题的根本原因。

另一个可能的错误原因是您正在使用视图，它们的行为与表格不同。

Oracle Select Query on many，Inner Query，Getting Not a Group Expression。来自JOIN的重复

1 个答案: