Oracle:获取所有月份的数据,如果没有数据则获取0

Question

我有一个Mview,通过idNumber和带来数据组Month.所以如果没有特定月份的数据,我想显示0.这是我的查询:

select MonthName, myCost, myNumber 
  from
     (
       select MONTH mm, myCost, myNumber
         from myOracle_mv
     ) myTotals,
     (
       select to_char(date '2012-12-1' + numtoyminterval(level,'month'), 'mm') MonthName
        from dual
      connect by level <= 12
     ) ALLMONTHS
where mm = MonthName

所以我期待:

Month Number Data
-----------------------
1     abc123 4444
2     0
3     abc123 4444
4     abc123 4444
5     0
6     abc123 4444
7     abc123 4444
8     0
9     abc123 4444
10    abc123 4444
11    0
12    abc123 4444

相反,我仍然得到:

1    abc123  4444
3    abc123  4444
4    abc123  4444
6    abc123  4444
7    abc123  4444
9    abc123  4444
10   abc123  4444
12   abc123  4444

有任何想法吗？

谢谢!

编辑:谢谢你的答案.我确实在我的查询中有外连接但忘记输入,因为集中在更改表/列的名称.

所以,是的,我尝试过OUTER JOIN,但仍然没有得到预期的结果.任何反馈都非常感谢.

编辑:这是myOracle_MV上的数据:

3777.24     AAA 1   2012
49973.12    AAA 2   2012
4049.91     AAA 3   2012
469.485     AAA 4   2012
5872.22     AAA 5   2012
65837.71    AAA 6   2012
566.23      AAA 7   2012
18432.95    AAA 8   2012
4337.75     AAA 12  2011
18811       BBB 1   2012
29872.67    BBB 2   2012
29068.55    BBB 3   2012
264957.8    BBB 4   2012
67673       BBB 5   2012
855.02      BBB 6   2012
5226.1      BBB 7   2012
2663.24     BBB 8   2012
5490.58     BBB 12  2011
3845.47     CCC 1   2012
3050.54     CCC 2   2012
3784.44     CCC 3   2012
799.73      CCC 4   2012
124884.2    CCC 5   2012
5157.24     CCC 6   2012
19184.78    CCC 7   2012
2280.05     CCC 8   2012
107.07      DDD 3   2012
181.78      DDD 4   2012
110.09      DDD 5   2012
18016.19    DDD 6   2012
1772.95     DDD 7   2012
63.32       DDD 8   2012

Answer 1

与现有答案非常相似,但是:

select months.month, mv.mycost, coalesce(mv.mynumber, 0) as mynumber
from (
  select to_char(date '1970-01-01'
    + numtoyminterval(level - 1, 'month'), 'mm') as month
  from dual
  connect by level <= 12) months
left join myoracle_mv mv
on mv.month = months.month
order by months.month, mv.mycost, mv.mynumber;

给出你发布的数据:

MONTH MYCOST   MYNUMBER
----- ------ ----------
01    AAA       3777.24 
01    BBB         18811 
01    CCC       3845.47 
02    AAA      49973.12 
02    BBB      29872.67 
02    CCC       3050.54 
03    AAA       4049.91 
03    BBB      29068.55 
03    CCC       3784.44 
03    DDD        107.07 
04    AAA       469.485 
04    BBB      264957.8 
04    CCC        799.73 
04    DDD        181.78 
05    AAA       5872.22 
05    BBB         67673 
05    CCC      124884.2 
05    DDD        110.09 
06    AAA      65837.71 
06    BBB        855.02 
06    CCC       5157.24 
06    DDD      18016.19 
07    AAA        566.23 
07    BBB        5226.1 
07    CCC      19184.78 
07    DDD       1772.95 
08    AAA      18432.95 
08    BBB       2663.24 
08    CCC       2280.05 
08    DDD         63.32 
09                    0 
10                    0 
11                    0 
12    AAA       4337.75 
12    BBB       5490.58 

 35 rows selected

如果要在mynumber列中显示零,则可以进行以下操作:

select months.month, mv.mycost, coalesce(mv.mynumber, 0) as mynumber

这使:

...
08    DDD         63.32 
09                    0 
10                    0 
11                    0 
12    AAA       4337.75 
...

从对Jafar答案的评论来看,听起来好像你自己已经走得那么远,但你想要mycost所有月份的所有值都是零值.如果是这种情况,那么您需要获取可能的值列表mycost以及外部联接.这将获取MV中的所有值:

select months.month, costs.mycost, coalesce(mv.mynumber, 0) as mynumber
from (
  select to_char(date '1970-01-01'
    + numtoyminterval(level - 1, 'month'), 'mm') as month
  from dual
  connect by level <= 12) months
cross join (
  select distinct mycost
  from myoracle_mv) costs
left join myoracle_mv mv
on mv.month = months.month
and mv.mycost = costs.mycost
order by months.month, costs.mycost, mv.mynumber;

并给出:

MONTH MYCOST   MYNUMBER
----- ------ ----------
01    AAA       3777.24 
01    BBB         18811 
01    CCC       3845.47 
01    DDD             0 
02    AAA      49973.12 
02    BBB      29872.67 
02    CCC       3050.54 
02    DDD             0 
03    AAA       4049.91 
03    BBB      29068.55 
03    CCC       3784.44 
03    DDD        107.07 
04    AAA       469.485 
04    BBB      264957.8 
04    CCC        799.73 
04    DDD        181.78 
05    AAA       5872.22 
05    BBB         67673 
05    CCC      124884.2 
05    DDD        110.09 
06    AAA      65837.71 
06    BBB        855.02 
06    CCC       5157.24 
06    DDD      18016.19 
07    AAA        566.23 
07    BBB        5226.1 
07    CCC      19184.78 
07    DDD       1772.95 
08    AAA      18432.95 
08    BBB       2663.24 
08    CCC       2280.05 
08    DDD         63.32 
09    AAA             0 
09    BBB             0 
09    CCC             0 
09    DDD             0 
10    AAA             0 
10    BBB             0 
10    CCC             0 
10    DDD             0 
11    AAA             0 
11    BBB             0 
11    CCC             0 
11    DDD             0 
12    AAA       4337.75 
12    BBB       5490.58 
12    CCC             0 
12    DDD             0 

 48 rows selected 

但希望你有另一个表可以保存可能的mycost值(假设它代表的是成本中心,而不是价格;稍微难以分辨什么),你可以使用它而不是子查询.

SQL小提琴.

另请注意,如果要添加过滤器,例如将数据限制为特定年份,则需要在left join子句中执行此操作,而不是作为where子句,或者将外部联接还原为内部联接.例如,添加以下内容:

where mv.year = 2011

意味着你只回来了两行:

MONTH MYCOST   MYNUMBER
----- ------ ----------
12    AAA       4337.75 
12    BBB       5490.58 

但是如果你在外部联接上创建了另一个条件,那么你仍然会得到48行,其中46行有零,两个有上面的值:

...
left join myoracle_mv mv
on mv.month = months.month
and mv.mycost = costs.mycost
and mv.year = 2011
order by months.month, costs.mycost, mv.mynumber;

...
11    CCC             0 
11    DDD             0 
12    AAA       4337.75 
12    BBB       5490.58 
12    CCC             0 
12    DDD             0 

 48 rows selected