使用 WITHIN GROUP 更新

Question

我写了下面的语句，其中 returns 我需要更新另一个格式的数据 table 但是我正在努力更新

SELECT element_id,
  LISTAGG(cast(0 as varchar2(20))||', '|| VALUE, ' | ') WITHIN GROUP (ORDER BY display_order)
FROM EDRN.MD$$_ELEMENT_VALUES
WHERE element_id IN
  (SELECT element_id FROM EDRN_NEW.DATA_DICTIONARY)
GROUP BY element_id;

我完成了基本的转换为 UPDATE 语句

    UPDATE EDRN_NEW.DATA_DICTIONARY
SET Choices = (LISTAGG(CAST(0 AS VARCHAR2(20))||', '|| VALUE, ' | ') WITHIN GROUP (ORDER BY display_order)
FROM EDRN.MD$$_ELEMENT_VALUES
WHERE element_id IN
  (SELECT element_id FROM EDRN_NEW.DATA_DICTIONARY)
GROUP BY element_id);

这收到了 "ORA-00934: group function is not allowed here" 错误。我不确定如何删除群组功能但保留我需要的数据格式？

Answer 1

您需要一个子查询才能使用 listagg()。在这种情况下，相关子查询：

update EDRN_NEW.DATA_DICTIONARY dd
    set choices = (SELECT LISTAGG(cast(0 as varchar2(20))||', '|| VALUE, ' | ') WITHIN GROUP (ORDER BY display_order)
                   FROM EDRN.MD$$_ELEMENT_VALUES ev
                   WHERE ev.element_id = dd.element_id
                  )
    where exists (select 1 
                  from EDRN.MD$$_ELEMENT_VALUES ev
                  where ev.element_id = dd.element_id 
                 );

使用 WITHIN GROUP 更新

UPDATE using a WITHIN GROUP

oracle

group-by

listagg