按天插入子查询日期

Question

我想插入基于日期的子查询。另外，每个日期只能使用四次。一旦达到第四次，第五个值将使用同一天的另一个日期。换句话说，使用下周星期一的日期。例如，Monday 和 6 JUNE 2016 到 Monday 和 13 JUNE 2016（您可以查看日历）。

我有一个查询，希望从presentation 表中获取基于presentationdatestart 和presentationdateend 的日期列表：

select   a.presentationid,
         a.presentationday,
         to_char (a.presentationdatestart + delta, 'DD-MM-YYYY', 'NLS_CALENDAR=GREGORIAN') list_date
from     presentation a,
         (select     level - 1 as delta
          from       dual
          connect by level - 1 <= (select max (presentationdateend - presentationdatestart)
                                   from   presentation))
where    a.presentationdatestart + delta <= a.presentationdateend
and      a.presentationday = to_char(a.presentationdatestart + delta, 'fmDay')
order by a.presentationdatestart + delta,
         a.presentationid; --IMPORTANT!!!--

例如，

presentationday    presentationdatestart    presentationdateend
     Monday              01-05-2016             04-06-2016
    Tuesday              01-05-2016             04-06-2016
   Wednesday             01-05-2016             04-06-2016
   Thursday              01-05-2016             04-06-2016

查询结果将列出01-05-2016 到04-06-2016 之间的所有可能日期：

Monday  02-05-2016
Tuesday 03-05-2016
Wednesday   04-05-2016
Thursday    05-05-2016
....
Monday      30-05-2016
Tuesday     31-05-2016
Wednesday   01-06-2016
Thursday    02-06-2016 (20 rows)

这是我的INSERT 查询：

insert into CSP600_SCHEDULE (studentID,
                             studentName, 
                             projectTitle,
                             supervisorID,
                             supervisorName,
                             examinerID,
                             examinerName,
                             exavailableID,
                             availableday,
                             availablestart,
                             availableend,
                             availabledate)   
select  '2013816591',
        'mong',
        'abc',
        '1004',
        'Sue',
        '1002',
        'hazlifah',
          2,
        'Monday', //BASED ON THIS DAY
        '12:00:00',
        '2:00:00',
         to_char (a.presentationdatestart + delta, 'DD-MM-YYYY', 'NLS_CALENDAR=GREGORIAN') list_date //FOR AVAILABLEDATE
from     presentation a,
         (select     level - 1 as delta
          from       dual
          connect by level - 1 <= (select max (presentationdateend - presentationdatestart)
                                   from   presentation))
where    a.presentationdatestart + delta <= a.presentationdateend
and      a.presentationday = to_char(a.presentationdatestart + delta, 'fmDay')
order by a.presentationdatestart + delta,
         a.presentationid;

此查询成功添加了 20 行，因为所有可能的日期都是 20 行。我想修改查询以便能够基于availableDay 插入，并且每个日期对于每个不同的studentID 只能使用四次。

CSP600_SCHEDULE 中的可能结果（我正在删除不相关的列以提高可读性）：

StudentID   StudentName     availableDay      availableDate
  2013         abc             Monday           01-05-2016
  2014         def             Monday           01-05-2016
  2015         ghi             Monday           01-05-2016
  2016         klm             Monday           01-05-2016
  2010         nop            Tuesday           02-05-2016
  2017         qrs            Tuesday           02-05-2016
  2018         tuv            Tuesday           02-05-2016
  2019         wxy            Tuesday           02-05-2016
  .....
  2039         rrr             Monday           09-05-2016
  ..... 

你可以查看日历:)

Answer 1

我认为您要求的是列出您的学生，然后将他们分成 4 组 - 然后将每批分配给一个日期。对吗？

在这种情况下，这样的事情应该可以工作（我使用表列表作为学生姓名，这样我就不需要将任何数据插入到自定义表中）：

WITH students AS
(SELECT table_name 
 FROM all_tables
 WHERE rownum < 100
 )
SELECT 
 table_name
,SYSDATE + (CEIL(rownum/4) -1)
FROM
 students
;

希望对你有帮助

...好吧，按照你的 cmets，我认为这可能是一个更好的解决方案：

WITH students AS
(SELECT table_name student_name
 FROM all_tables
 WHERE rownum < 100
 )
, dates AS
(SELECT TRUNC(sysdate) appointment_date from dual UNION
 SELECT TRUNC(sysdate+2) from dual UNION
 SELECT TRUNC(sysdate+4) from dual UNION
 SELECT TRUNC(sysdate+6) from dual UNION
 SELECT TRUNC(sysdate+8) from dual UNION
 SELECT TRUNC(sysdate+10) from dual UNION
 SELECT TRUNC(sysdate+12) from dual UNION
 SELECT TRUNC(sysdate+14) from dual 
)
SELECT 
 s.student_name
,d.appointment_date
FROM
 --get a list of students each with a sequential row number, ordered by student name 
 (SELECT
   student_name
  ,ROW_NUMBER() OVER (ORDER BY student_name) rn
 FROM students
 )     s
 --get a list of available dates with a sequential row number, ordered by date
,(SELECT
   appointment_date
  ,ROW_NUMBER() OVER (ORDER BY appointment_date) rn
 FROM dates
 ) d
WHERE 1=1
--allocate the first four students to date rownumber1, next four students to date rownumber 2...
AND CEIL(s.rn/4) = d.rn 
;