Question

Can you help me to solve this error

The type of column “nvrchildgender” conflicts with the type of other columns specified in the UNPIVOT list.

Table structure:

CREATE TABLE [dbo].[tblHRIS_ChildDetails](
    [intCHID] [int],
    [intSID] [int] NOT NULL,
    [nvrChildname] [nvarchar](250) NULL,
    [nvrChildGender] [nvarchar](50) NULL,
    [dttChildDOB] [datetime] NULL,
    [nvrnominee] [nvarchar](50) NULL,
    [nvrChildOccupation] [nvarchar](250) NULL,
    [dttCreatedon] [datetime] NULL,
    [dttModifiedOn] [datetime] NULL,
    [nvrModifiedby] [nvarchar](50) NULL
) ON [PRIMARY]

Query:

select *
from
(
  select value, col+'_'+cast(rn as varchar(10)) col
  from
  (
    select nvrchildname,
      nvrchildgender,
      convert(nvarchar(10), dttchildDOB, 120) dttchildDOB,
      nvrchildoccupation,
      row_number() over(partition by intsid order by intCHID) rn
    from tblHRIS_ChildDetails
    where intsid = 463
  ) src
  unpivot
  (
    value 
    for col in (nvrchildname, nvrchildgender, dttchildDOB,  nvrchildoccupation)
  ) 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

I cannot to able to run this query i think some cast problem pls resolve.

Sql fiddle

Answer 1

To UNPIVOT successfully, the column types must match. Since two of the 4 columns are already nvarchar(250) and the other two shorter, promoting them to nvarchar(250) is the most expedient fix.

select *
from
(
  select value, col+'_'+cast(rn as varchar(10)) col
  from
  (
    select nvrchildname,
      cast(nvrchildgender as nvarchar(250)) nvrgender,
      convert(nvarchar(250), dttchildDOB, 120) dttchildDOB,
      nvrchildoccupation 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

Note: You have named the PIVOT column nvrgender but the base column was nvrchildgender. Same problem with mismatched occupation column naming between pivot and unpivot.