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rækker i kolonner

For denne type data skal du implementere både UNPIVOT og derefter PIVOT funktioner i SQL Server. UNPIVOT tager dine data fra de flere kolonner og placerer dem i to kolonner, og derefter anvender du PIVOT at transformere dataene tilbage til kolonner.

Hvis du kender alle de værdier, du vil transformere, så kan du hardkode det, svarende til dette:

select *
from
(
  select value, col+'_'+cast(rn as varchar(10)) col
  from
  (
    select nvrchildname,
      nvrgender,
      convert(varchar(10), dttchildDOB, 120) dttchildDOB,
      occupation,
      row_number() over(partition by intsid order by intCHID) rn
    from tblHRIS_ChildDetails
    where intsid = 463
  ) src
  unpivot
  (
    value 
    for col in (nvrchildname, nvrgender, dttchildDOB, occupation)
  ) unpiv
) src1
pivot
(
  max(value)
  for col in ([nvrchildname_1], [nvrgender_1], 
              [dttchildDOB_1], [occupation_1], 
              [nvrchildname_2], [nvrgender_2], 
              [dttchildDOB_2], [occupation_2]) 
) piv

Se SQL Fiddle with Demo

Hvis du nu har et ukendt antal værdier at transformere, så kan du bruge dynamisk SQL til dette:

DECLARE @colsUnpivot AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX),
    @colsPivot as  NVARCHAR(MAX)

select @colsUnpivot = stuff((select ','+quotename(C.name)
         from sys.columns as C
         where C.object_id = object_id('tblHRIS_ChildDetails') and
               C.name not in ('intCHID', 'intsid')
         for xml path('')), 1, 1, '')

select @colsPivot = STUFF((SELECT  ',' 
                      + quotename(c.name 
                         +'_'+ cast(t.rn as varchar(10)))
                    from 
                    (
                      select row_number() over(partition by intsid order by intCHID) rn
                      from tblHRIS_ChildDetails
                    ) t
                    cross apply sys.columns as C
                   where C.object_id = object_id('tblHRIS_ChildDetails') and
                         C.name not in ('intCHID', 'intsid')
                   group by c.name, t.rn
                   order by t.rn
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query 
  = 'select *
      from
      (
        select col+''_''+cast(rn as varchar(10)) col, value
        from 
        (
          select nvrchildname,
            nvrgender,
            convert(varchar(10), dttchildDOB, 120) dttchildDOB,
            occupation,
            row_number() over(partition by intsid order by intCHID) rn
          from tblHRIS_ChildDetails
          where intsid = 463
        ) x
        unpivot
        (
          value
          for col in ('+ @colsunpivot +')
        ) u
      ) x1
      pivot
      (
        max(value)
        for col in  ('+ @colspivot +')
      ) p'

exec(@query)

Se SQL Fiddle with Demo

Resultatet af begge forespørgsler er:

| NVRCHILDNAME_1 | NVRGENDER_1 | DTTCHILDDOB_1 | OCCUPATION_1 | NVRCHILDNAME_2 | NVRGENDER_2 | DTTCHILDDOB_2 | OCCUPATION_2 |
-----------------------------------------------------------------------------------------------------------------------------
|             SK |      Female |    2001-12-11 |     Studying |             SM |        Male |    2007-10-08 |      Student |


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