PL/SQL 中的列表答案

【问题标题】：LISTAGG IN PL/SQLPL/SQL 中的列表
【发布时间】：2015-04-23 06:17:58
【问题描述】：

帮助请在创建函数时发现错误，该函数将从列表中返回一行。

SELECT   listagg(' ' || V_RECEIVING_LIST.DOCUMENT_NUMBER || CHR(13))
         WITHIN GROUP (ORDER BY V_RECEIVING_LIST.DOCUMENT_NUMBER)
FROM     svc.claim_detail, tbc.v_receiving_list
WHERE    claim_detail.id_claim = 334455 
         AND V_RECEIVING_LIST.ID_RECEIVING_LIST = CLAIM_DETAIL.ID_RECEIVING_LIST

代码返回正确的结果。

但下一个不返回相同的。

DECLARE
    scodes   VARCHAR2 (4000);
BEGIN
    SELECT (LISTAGG(' ' || RECEIVING_LIST.DOCUMENT_NUMBER || CHR(13))
           WITHIN GROUP (ORDER BY RECEIVING_LIST.DOCUMENT_NUMBER))
    INTO   scodes 
    FROM   svc.claim_detail, tbc.v_receiving_list  
    WHERE  claim_detail.id_claim = 334455 
         AND RECEIVING_LIST.ID_RECEIVING_LIST = CLAIM_DETAIL.ID_RECEIVING_LIST;
    DBMS_OUTPUT.PUT_LINE(scodes);
END;

【问题讨论】：

PL/SQL 块显示什么？ SQL 查询返回什么？
您下面的示例“答案”仅显示一行输出（我可以看到）。所以有什么问题？与您在下面的答案不同的独立 SQL 返回是什么？

标签： plsql listagg

【解决方案1】：

SQL> select * from V_RECEIVING_LIST ;

DOCUMENT_NUMBER ID_RECEIVING_LIST
--------------- --------------------
              1 a
              1 a
              2 b

SQL> select * from claim_detail ;

  ID_CLAIM ID_RECEIVING_LIST
---------- --------------------
       123 a
       123 a
       124 b


SQL> DECLARE
  2      scodes   VARCHAR2 (4000);
  3  BEGIN
  4      SELECT (LISTAGG(' '|| v_receiving_list.DOCUMENT_NUMBER || CHR(13))
  5             WITHIN GROUP (ORDER BY v_receiving_list.DOCUMENT_NUMBER))
  6
  7      INTO   scodes
  8      FROM   claim_detail, v_receiving_list
  9      WHERE  claim_detail.id_claim = 123
 10      AND v_receiving_list.ID_RECEIVING_LIST = CLAIM_DETAIL.ID_RECEIVING_LIST;
 11
 12
 13      DBMS_OUTPUT.PUT_LINE('The output is '||scodes);
 14  END;
 15  /
 1e output is  1

PL/SQL procedure successfully completed.

【讨论】：