SQL QUERY不返回ORACLE APEX CLASSIC REPORT的数据

Question

我在Oracle application Express 4.2中有一个SQL查询(PL/SQL函数体返回SQL查询).我创建了一个经典报告,这是我在下面使用的查询.我的查询当前工作正常但我需要使用另一个查询更新此函数中的现有查询,当我尝试更改查询时它不起作用.我究竟做错了什么？任何帮助表示赞赏.

以下是我的工作查询:

declare
  a_query varchar2(5000);
  this_strin varchar2(50);
begin
  a_query := 'select flight_nmbr, sequence_nmbr '||
         'from flights '||
         'where sequence_nmbr >= 0 and data_version_name = ''' ||
    :P3_DATA_VERSION || '''';
  if :P3_SEARCH_NUMBER is not null then
    if instr(:P3_SEARCH_NUMBER, '%') > 0 then
      this_strin := :P3_SEARCH_NUMBER;
  else
      this_strin := '%'||:P3_SEARCH_NUMBER||'%';
  end if;
  a_query := a_query||chr(10)||
            ' and flight_nmbr like '''|| upper(this_strin) ||'''';
  end if;
  return a_query;
    end;

我需要将此函数内的查询更新为以下内容:

SELECT FLIGHT_NMBR, SCHEDULED_LAUNCH_DATE
FROM FLIGHTS
WHERE DATA_VERSION_NAME = 'WORKING' AND
  sequence_nmbr >= 0
ORDER BY (CASE WHEN to_date(scheduled_launch_date, 'DD-MON-YY') 
BETWEEN add_months(trunc(sysdate, 'MON'), 0) 
AND add_months(trunc(sysdate, 'MON'), 6) THEN 1 ELSE 2 END),
     (CASE WHEN to_date(scheduled_launch_date, 'DD-MON-YY') 
BETWEEN add_months(trunc(sysdate, 'MON'), 0) 
     AND add_months(trunc(sysdate, 'MON'), 6) 
THEN SCHEDULED_LAUNCH_DATE END),
     sequence_nmbr;

我试着自己这样做,这就是我在下面得到的(这不起作用):

   declare
       a_query varchar2(5000);
    this_strin varchar2(50);
   begin
      a_query := 'select flight_nmbr, sequence_nmbr '||
         'from flights '||
         'where sequence_nmbr >= 0 and data_version_name = ''' ||
         'ORDER BY (CASE WHEN to_date(scheduled_launch_date, 'DD-MON-YY'
          BETWEEN add_months(trunc(sysdate, 'MON'), 0) 
          AND add_months(trunc(sysdate, 'MON'), 6) THEN 1 ELSE 2 END),
          (CASE WHEN to_date(scheduled_launch_date, 'DD-MON-YY') BETWEEN 
           add_months(trunc(sysdate, 'MON'), 0) 
     AND add_months(trunc(sysdate, 'MON'), 6) THEN
             SCHEDULED_LAUNCH_DATE END),
             sequence_nmbr' ||
      :P3_DATA_VERSION || '''';
        if :P3_SEARCH_NUMBER is not null then
        if instr(:P3_SEARCH_NUMBER, '%') > 0 then
           this_strin := :P3_SEARCH_NUMBER;
        else
             this_strin := '%'||:P3_SEARCH_NUMBER||'%';
        end if;
          a_query := a_query||chr(10)||
            ' and flight_nmbr like '''|| upper(this_strin) ||'''';
        end if;
         return a_query;
          end;

Answer 1

它不起作用,因为'查询中有很多符号.你需要复制每个引用(你只为第一个和最后一个做了这个),或者使用以下技巧:

a_query := q'[SELECT FLIGHT_NMBR, SCHEDULED_LAUNCH_DATE
    FROM FLIGHTS
    WHERE DATA_VERSION_NAME = 'WORKING' AND
      sequence_nmbr >= 0
    ORDER BY (CASE WHEN to_date(scheduled_launch_date, 'DD-MON-YY') 
    BETWEEN add_months(trunc(sysdate, 'MON'), 0) 
    AND add_months(trunc(sysdate, 'MON'), 6) THEN 1 ELSE 2 END),
         (CASE WHEN to_date(scheduled_launch_date, 'DD-MON-YY') 
    BETWEEN add_months(trunc(sysdate, 'MON'), 0) 
         AND add_months(trunc(sysdate, 'MON'), 6) 
    THEN SCHEDULED_LAUNCH_DATE END),
         sequence_nmbr]';

内部的文本q'[ ... ]'可以包含单个qoutes,并且将被视为内部有qoutes的字符串值.

UPD
一个小例子来说明这个想法:

select q'[I'm here]' text from dual;

TEXT   
--------
I'm here