Question

我想采取以下查询

select '2009042 Restraint 151214.pdf', 
       '2009042 Restraint 170215.pdf',
       '2009042 Restraint 240215.pdf',
       '2009856 Restraint 190215.pdf',
       '208272 Notice 120215.pdf',
       '208272 Restraint 120215.pdf',
       '212598 Restraint 160215.pdf',
       '213195 Notice 130215.pdf'
from   dual

并将其转换为一个查询，该查询将上述查询中的列作为行返回。 pivot声明似乎无法做到这一点。

所以我想返回行：

COL1
2009042 Restraint 151214.pdf
2009042 Restraint 170215.pdf
2009042 Restraint 240215.pdf
2009856 Restraint 190215.pdf
208272 Notice 120215.pdf
208272 Restraint 120215.pdf
212598 Restraint 160215.pdf
213195 Notice 130215.pdf

请注意，与inverse row to column

略有不同

Answer 1

枢轴声明似乎无法做到这一点。

是的，因为您并未尝试将行转移到列中，而是在尝试将从列中取消 行。

如果您的列具有预定义的枚举名称，则可以使用UNPIVOT，如下所示：

select *
from (
  select '2009042 Restraint 151214.pdf' v1, 
         '2009042 Restraint 170215.pdf' v2,
         '2009042 Restraint 240215.pdf' v3,
         '2009856 Restraint 190215.pdf' v4,
         '208272 Notice 120215.pdf'     v5,
         '208272 Restraint 120215.pdf'  v6,
         '212598 Restraint 160215.pdf'  v7,
         '213195 Notice 130215.pdf'     v8
  from   dual
) t
unpivot (
  col1 for v in (v1, v2, v3, v4, v5, v6, v7, v8)
)

产量：

V   COL1
--------------------------------
V1  2009042 Restraint 151214.pdf
V2  2009042 Restraint 170215.pdf
V3  2009042 Restraint 240215.pdf
V4  2009856 Restraint 190215.pdf
V5  208272 Notice 120215.pdf
V6  208272 Restraint 120215.pdf
V7  212598 Restraint 160215.pdf
V8  213195 Notice 130215.pdf

如果没有这样的名称可用，事情会变得多毛，但仍然可行（可能取决于Oracle中没有明确定义的列命名约定）：

select *
from (
  select '2009042 Restraint 151214.pdf', 
         '2009042 Restraint 170215.pdf',
         '2009042 Restraint 240215.pdf',
         '2009856 Restraint 190215.pdf',
         '208272 Notice 120215.pdf',
         '208272 Restraint 120215.pdf',
         '212598 Restraint 160215.pdf',
         '213195 Notice 130215.pdf'
  from   dual
) t
unpivot (
  col1 for v in (
    "'2009042RESTRAINT151214.PDF'", 
    "'2009042RESTRAINT170215.PDF'", 
    "'2009042RESTRAINT240215.PDF'", 
    "'2009856RESTRAINT190215.PDF'", 
    "'208272RESTRAINT120215.PDF'", 
    "'208272NOTICE120215.PDF'", 
    "'212598RESTRAINT160215.PDF'", 
    "'213195NOTICE130215.PDF'"
  )
)

产量：

V                               COL1
------------------------------------------------------------
'2009042RESTRAINT151214.PDF'    2009042 Restraint 151214.pdf
'2009042RESTRAINT170215.PDF'    2009042 Restraint 170215.pdf
'2009042RESTRAINT240215.PDF'    2009042 Restraint 240215.pdf
'2009856RESTRAINT190215.PDF'    2009856 Restraint 190215.pdf
'208272RESTRAINT120215.PDF'     208272 Restraint 120215.pdf
'208272NOTICE120215.PDF'        208272 Notice 120215.pdf
'212598RESTRAINT160215.PDF'     212598 Restraint 160215.pdf
'213195NOTICE130215.PDF'        213195 Notice 130215.pdf

当然，如果您准备编写那么多SQL，为什么不使用UNION ALL，as Gordon suggested

Answer 2

首先将查询短语称为联合：

select '2009042 Restraint 151214.pdf' from dual union all
select '2009042 Restraint 170215.pdf' from dual union all
select '2009042 Restraint 240215.pdf' from dual union all
select '2009856 Restraint 190215.pdf' from dual union all
select '208272 Notice 120215.pdf' from dual union all
select '208272 Restraint 120215.pdf' from dual union all
select '212598 Restraint 160215.pdf' from dual union all
select '213195 Notice 130215.pdf' from dual

Answer 3

快速执行此操作的方法是使用以下Oracle system defined type，sys.odcivarchar2list：

select column_value col1 
from table(sys.odcivarchar2list(
       '2009042 Restraint 151214.pdf', 
       '2009042 Restraint 170215.pdf',
       '2009042 Restraint 240215.pdf',
       '2009856 Restraint 190215.pdf',
       '208272 Notice 120215.pdf',
       '208272 Restraint 120215.pdf',
       '212598 Restraint 160215.pdf',
       '213195 Notice 130215.pdf'));

返回：

COL1                                                                           
--------------------------------------------------------------------------------
2009042 Restraint 151214.pdf                                                    
2009042 Restraint 170215.pdf                                                    
2009042 Restraint 240215.pdf                                                    
2009856 Restraint 190215.pdf                                                    
208272 Notice 120215.pdf                                                        
208272 Restraint 120215.pdf                                                     
212598 Restraint 160215.pdf                                                     
213195 Notice 130215.pdf

如果你想使用数值，那么sys.odcinumberlist()，以及上面链接的Oracle doc中记录的其他数据。

Oracle SQL将具有多个列的单行转换为多行

3 个答案: