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SQL Server 2008 R2 using PIVOT with varchar columns not working

I'm using SQL Server 2008 R2, I have this simple table

enter image description here

What I was trying to do is make a selection from this table and get this following result

x |      1     |       2     |      3
--+------------+-------------+------------
1 |   first 1  |    first 2  |    first 3
2 |   Second 1 |    second 2 |    second 3 

I thought that can be done with PIVOT

I don't know much about PIVOT AND all my search result found using PIVOT with Count() . SUM(), AVG() which will not work in my table since I'm trying to PIVOT on a varchar column

Question am I using the right function? Or is there something else I need to know to solve this issue? Any help will be appreciated

I tried this with no luck

PIVOT(count(x) FOR value IN ([1],[2],[3]) )as total 
PIVOT(count(y) FOR value IN ([1],[2],[3]) )as total  // This one is the nearest 
of what i wand  but instead of the column value values i get 0  

Here is the query if any one to test it

CREATE TABLE #test (x int , y int , value Varchar(50))
INSERT INTO #test VALUES(1,51,'first 1')
INSERT INTO #test VALUES(1,52,'first 2')
INSERT INTO #test VALUES(1,53,'first 3')
INSERT INTO #test VALUES(2,51,'Second 1')
INSERT INTO #test VALUES(2,52,'Second 2')
INSERT INTO #test VALUES(2,53,'Second 3')
SELECT * FROM #test
  PIVOT(count(y) FOR value IN ([1],[2],[3]) )as total 
 DROP TABLE #test 
like image 850
Mina Gabriel Avatar asked Jun 08 '26 14:06

Mina Gabriel


1 Answers

When you are using the PIVOT function the values inside the IN clause need to match a value that you are selecting. Your current data does not include 1, 2, or 3. You can use row_number() to assign a value for each x:

select x, [1], [2], [3]
from
(
  select x, value,
    row_number() over(partition by x order by y) rn
  from test
) d
pivot
(
  max(value)
  for rn in ([1], [2], [3])
) piv;

See SQL Fiddle with Demo. If you then have a unknown number of values for each x, then you will want to use dynamic SQL:

DECLARE @cols AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT distinct ',' + QUOTENAME(row_number() over(partition by x order by y)) 
                    from test
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT x,' + @cols + ' 
            from 
            (
              select x, value,
                row_number() over(partition by x order by y) rn
              from test
            ) x
            pivot 
            (
                max(value)
                for rn in (' + @cols + ')
            ) p '

execute(@query);

See SQL Fiddle with Demo

like image 64
Taryn Avatar answered Jun 11 '26 06:06

Taryn