Oracle LISTAGG 和 Coalesce

Question

我已经浓缩了以下 table EPS_PROPOSAL_EXT_T：

+--------------------+------------+------------+
| PROPOSAL_NUMBER    |ONR_OPTION_1|ONR_Option_2|   ...
+--------------------+------------+------------+
|        1234        |      N     |      N     |   ...
|        1235        |      Y     |      Y     |   ...
|        1236        |      N     |      Y     |   ... 
+--------------------+------------+------------+

这里的问题是我需要对所有这些不同的 ONR_Options 执行 LISTAGG，但我不能让它们显示为 'Y'。我需要用人类可以理解的东西替换 'Y' 的那些。请参阅下面我尝试执行此操作的 SELECT 声明：

SELECT eps.PROPOSAL_NUMBER, eps.TITLE, per.FULL_NAME, ext.NRP_IREF_CD, ext.RESEARCH_TYPE_CD, 
nsf.NSF_CODE, ext.NPS_THRUST_DESCRIPTION,
   CASE
        WHEN ext.ONR_Option_1 = 'Y' THEN 'Option 1'
        WHEN ext.ONR_Option_2 = 'Y' THEN 'Option 2'
        WHEN ext.ONR_Option_3 = 'Y' THEN 'Option 3'
        WHEN ext.ONR_Option_4 = 'Y' THEN 'Option 4'
        WHEN ext.ONR_Option_5 = 'Y' THEN 'Option 5'
        WHEN ext.ONR_Option_6 = 'Y' THEN 'Option 6'
        WHEN ext.ONR_Option_7 = 'Y' THEN 'Option 7'
        WHEN ext.ONR_Option_8 = 'Y' THEN 'Option 8'
        WHEN ext.ONR_Option_9 = 'Y' THEN 'Option 9' 
        WHEN ext.ONR_NOT_APPLICABLE = 'Y' THEN 'Not Applicable'
        ELSE ''
   END ONR
FROM EPS_PROPOSAL eps
LEFT JOIN EPS_PROPOSAL_EXT_T ext
    ON eps.PROPOSAL_NUMBER = ext.PROPOSAL_NUMBER
LEFT JOIN EPS_PROP_PERSON per
    ON eps.PROPOSAL_NUMBER = per.PROPOSAL_NUMBER AND
      (per.PROP_PERSON_ROLE_ID = 'PI' OR per.PROP_PERSON_ROLE_ID = 'PD')
LEFT JOIN EPS_PROP_ABSTRACT abs
    ON eps.PROPOSAL_NUMBER = abs.PROPOSAL_NUMBER
LEFT JOIN NSF_CODES nsf
    ON eps.NSF_CODE = nsf.NSF_SEQUENCE_NUMBER
WHERE eps.OWNED_BY_UNIT = '401' AND eps.requested_start_date_initial >= DATE '2019-10-01';

这可行，但您可以看到它的问题，对吗？我设置 CASE 语句的方式不会考虑特定 PROPOSAL_NUMBER 有多个 ONR_Option 即 TRUE.

在我上面给出的示例中，如果我搜索编号为 1235 的提案； ONR 结果应该是 - 'Option 1, Option 2'.

如何解决 LISTAGG 和 COALESCE 的这个难题？或者这是解决这个问题的方法？

Answer 1

LISTAGG 在这里没有帮助。为什么？因为你的数据模型错误。在我看来，应该是这样的：

SQL> with test (prop, onr, status) as
  2    (select 1234, '1', 'N' from dual union all
  3     select 1234, '2', 'N' from dual union all
  4     select 1234, '3', 'Y' from dual union all
  5     select 1235, '1', 'Y' from dual union all
  6     select 1235, '2', 'Y' from dual union all
  7     select 1235, '3', 'N' from dual
  8    )
  9  select prop,
 10    listagg(case when status = 'Y' then 'Option ' || onr end, ',')
 11      within group (order by onr) as result
 12  from test
 13  group by prop;

      PROP RESULT
---------- ------------------------------
      1234 Option 3
      1235 Option 1,Option 2

SQL>

目前的情况，看看这是否 - CASE 的连接数与 table 中的 ONR_OPTION 列一样多，它可以像山羊一样缩放喜欢教飞行，以及删除多个逗号的痛苦 - 帮助：

SQL> with test (prop, onr_1, onr_2, onr_3) as
  2    (select 1234, 'N', 'N', 'Y' from dual union all
  3     select 1235, 'Y', 'Y', 'N' from dual
  4    )
  5  select prop,
  6    trim(both ',' from
  7          case when onr_1 = 'Y' then 'Option 1' else null end ||','||
  8          case when onr_2 = 'Y' then 'Option 2' else null end ||','||
  9          case when onr_3 = 'Y' then 'Option 3' else null end
 10         ) as result
 11  from test;

      PROP RESULT
---------- ------------------------------
      1234 Option 3
      1235 Option 1,Option 2

SQL>

Oracle LISTAGG 和 Coalesce

Oracle LISTAGG and Coalesce

oracle

left-join

case

coalesce

listagg