选择 DISTINCT 结果后的字符串连接

Question

我有以下查询：

SELECT xmlagg(xmlparse(content RESULTS || '|' wellformed) ORDER BY RESULTS).getclobval() AS RESULTS 
FROM
(
  SELECT distinct ' '   || result|| ' - '   || result_final || ' xxx' as RESULTS from myTable where ID = '123456'
);

目前“xxx”会附加在每个result_final的末尾，如何通过将其连接到查询的最终字符串的开头来实现？

' xxx'|| RESULTS

有条件，只有当result=x时才会发生上述连接，否则只打印RESULTS。

Answer 1

将该字符串移到“结果”前面而不是后面。

不过，由于应该满足附加条件，请使用您当前的查询（没有 'xxx'）作为子查询并通过 CASE.

应用条件

使用虚拟样本数据：

SQL> DESC mytable
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 RESULT                                             CHAR(1)
 RESULT_FINAL                                       CHAR(1)
 ID                                                 CHAR(6)

SQL> SELECT * FROM mytable;

R R ID
- - ------
x y 123456

SQL> SELECT CASE
  2            WHEN TO_CHAR (results) = 'x' THEN ' xxx' || results
  3            ELSE results
  4         END AS results
  5    FROM (SELECT XMLAGG (XMLPARSE (CONTENT RESULTS || '|' WELLFORMED)
  6                         ORDER BY RESULTS).getclobval () AS RESULTS
  7            FROM (SELECT DISTINCT
  8                         ' ' || result || ' - ' || result_final AS RESULTS
  9                    FROM myTable
 10                   WHERE ID = '123456'));

RESULTS
--------------------------------------------------------------------------------
 x - y|

SQL>

选择 DISTINCT 结果后的字符串连接

String concatenation after DISTINCT result selected

oracle

distinct

nsxmlparser