Convert rows into columns sql server - sql

Question

I want to convert rows into columns.
Column1 Column2 Column3 Column4 Column5 Column6 Column7
1 2016-07-25 7 3 c1 c11 c111
2 2016-07-26 5 2 c2 c22 c222
3 2016-07-27 1 2 c3 c33 c333
4 2016-07-28 3 1 c4 c44 c444
I want output as follows :
Column1 1 2 3 4
Column2 2016-07-25 2016-07-26 2016-07-27 2016-07-28
Column3 7 5 1 3
Column4 3 2 2 1
Column5 c1 c2 c3 c4
Column6 c11 c22 c33 c44
Column7 c111 c222 c333 c44
I tried to do it using pivot unpivot but did not find proper solution.
First Table (input) can have n number of rows.

Answer 1

You need to use UNPIVOT, then PIVOT and if columns number is unknown - dynamic SQL:
DECLARE #columns nvarchar(max),
#columns_with_convert nvarchar(max),
#row_numbers nvarchar(max),
#sql nvarchar(max)
SELECT #columns = STUFF((
SELECT ','+QUOTENAME(name)
FROM sys.columns
WHERE [object_id] = OBJECT_ID('##YourTable')
FOR XML PATH('')),1,1,'')
--Will get you [Column1],[Column2],[Column3],[Column4],[Column5],[Column6],[Column7]
SELECT #columns_with_convert = (
SELECT 'CAST('+QUOTENAME(name)+' as nvarchar(max)) as '+QUOTENAME(name) +','
FROM sys.columns
WHERE [object_id] = OBJECT_ID('##YourTable')
FOR XML PATH(''))
--Will get you CAST([Column1] as nvarchar(max)) as [Column1], ... because all rows must be same datatype.
SELECT #row_numbers = STUFF((
SELECT ','+ QUOTENAME(CAST(ROW_NUMBER() OVER (ORDER BY (SELECT 1)) as nvarchar(max)))
FROM ##YourTable
FOR XML PATH('')),1,1,'')
--This will be used when PIVOTing ([1],[2],[3],[4])
SELECT #sql = '
SELECT *
FROM (
SELECT RN,
[Columns],
[Values]
FROM (
SELECT '+#columns_with_convert+'
ROW_NUMBER() OVER (ORDER BY (SELECT 1)) as RN
FROM ##YourTable
) as p
UNPIVOT (
[Values] FOR [Columns] IN ('+#columns+')
) as unpvt
) as s
PIVOT (
MAX([Values]) FOR RN IN ('+#row_numbers+')
) as pvt
'
EXEC sp_executesql #sql
Output:
Columns 1 2 3 4
Column1 1 2 3 4
Column2 2016-07-25 2016-07-26 2016-07-27 2016-07-28
Column3 7 5 1 3
Column4 3 2 2 1
Column5 c1 c2 c3 c4
Column6 c11 c22 c33 c44
Column7 c111 c222 c333 c444
If you PRINT #sql you will get a text of query:
SELECT *
FROM (
SELECT RN,
[Columns],
[Values]
FROM (
SELECT CAST([Column1] as nvarchar(max)) as [Column1],CAST([Column2] as nvarchar(max)) as [Column2],CAST([Column3] as nvarchar(max)) as [Column3],CAST([Column4] as nvarchar(max)) as [Column4],CAST([Column5] as nvarchar(max)) as [Column5],CAST([Column6] as nvarchar(max)) as [Column6],CAST([Column7] as nvarchar(max)) as [Column7],
ROW_NUMBER() OVER (ORDER BY (SELECT 1)) as RN
FROM ##YourTable
) as p
UNPIVOT (
[Values] FOR [Columns] IN ([Column1],[Column2],[Column3],[Column4],[Column5],[Column6],[Column7])
) as unpvt
) as s
PIVOT (
MAX([Values]) FOR RN IN ([1],[2],[3],[4])
) as pvt

Answer 2

I tried to do it using pivot unpivot but did not find proper solution.
First Table (input) can have n number of rows.
The reason why it didn't work is because PIVOT does not work for dynamic number of rows. Meaning the syntax can transpose only a fixed number of Rows as Columns and you need to specify that in the query. It cannot Dynamically auto generate columns on the fly based on the values in your rows.
Edit:
One Solution I found for dynamic pivot (1st result from google search) : https://www.mssqltips.com/sqlservertip/2783/script-to-create-dynamic-pivot-queries-in-sql-server/
It needs dynamic SQL (there is no other option)

Answer 3

DECLARE #TABLE TABLE
(RowNo INT,Col1 VARCHAR(10),Col2 VARCHAR(10)
,Col3 VARCHAR(10))
INSERT INTO #TABLE VALUES
(1,'A','B','C')
SELECT Kishore from #Table
Unpivot(Kishore For Value IN (Col1,Col2,Col3)) AS H